Critical Reasoning Flashcards
Argument Structure - list all the possible parts of an argument
e.g., The expansion of the runways at the Bay City Airport will allow larger planes to use the airport. These new planes will create a lot of noise, a nuisance for residents who live near the airport. However, many of the residents in this neighbourhood work in construction, and the contract to expand the runways has been awarded to the local construction company. Thus, the expansion of the runways will lead to an increased quality of life for the residents of this neighbourhood.
1) Premise (at least 1) - information to SUPPORT some claim or conclusion (reasons).
> e.g., “However, many of the residents in this neighbourhood work in construction, and the contract to expand the runways has been awarded to the local construction company.”
- (Most will have a) Conclusion - The primarily claim the author is trying to PROVE or the OUTCOME of a plan someone is proposing.
> The “claimed” result (perhaps in the future, “will”).
> NOT a statement of fact.
> e.g., “Thus, the expansion of the runways will lead to an increased quality of life for the residents of this neighbourhood.” - (Most will contain) Background Info - context to understand the basic situation, neither supports nor goes against the conclusion.
> Almost always fact-based (such as descriptions of plans/ideas, historical info, data, definitions of words or concepts).
> e.g., “The expansion of the runways at the Bay City Airport will allow larger planes to use the airport.” - (Some will contain) Counterpoints - info that goes against the author’s conclusion.
> e.g., “These new planes will create a lot of noise, a nuisance for residents who live near the airport.” - (Many will rely on) Assumptions - not stated in the argument, but that the author must BELIEVE TO BE TRUE in order to draw the given conclusion.
- Intermediate conclusion - first conclusion that is supported by other premises and in turn SUPPORTS a FURTHER CONCLUSION
> Premise supports the intermediate conclusion, which then supports the final conclusion.
> therefore, Intermediate conclusions are both a claim and a premise.
Keywords for Conclusion
Thus, therefore, it follows that, hence
Clearly
__shows that__
So
Surely
Conclusion:
> usually an opinion/claim (prediction about the future), not a fact
> This is what the author is trying to prove
Keywords for Premise
Because of
Since
Due to
As a result of
After all
For
Premise:
> Can be a fact
> Premises SUPPORT the author’s conclusion or DEPENDED on
Claims versus Facts
Claims - predictions about the future, not facts. Claims are good candidates to be the conclusion.
How to tell whether a statement is an Intermediate Conclusion or (Final) Conclusion?
Use the Therefore Test
BECAUSE _intermediate conclusion__, THEREFORE __final conclusion.
Or vice versa (switch statement order).
Which order makes sense?
e.g., Because he is likely to get caught, therefore he will probably end up in jail.
Example: Label the parts of the argument
The owner of a small publishing company plans to lease a new office space that has floor-to-ceiling windows and no internal walls, arguing that the new space will enhance worker productivity. The owner cites a recent study showing that workers exposed to natural light throughout the day tended to report, on average, a higher level of job satisfaction than did those who worked in office spaces that used fluorescent lighting. Thus, the owner concluded, exposure to natural light has a positive effect on workers’ job satisfaction.
“The owner of a small publishing company plans to lease a new office space that has floor-to-ceiling windows and no internal walls,” => Background info
“…arguing that the new space will enhance worker productivity” => Conclusion
“The owner cites a recent study showing that workers exposed to natural light throughout the day tended to report, on average, a higher level of job satisfaction than did those who worked in office spaces that used fluorescent lighting. “ => Premise
“Thus, the owner concluded, exposure to natural light has a positive effect on workers’ job satisfaction.” => intermediate conclusion
Intermediate vs Conclusion? Therefore Test
> BECAUSE the new space will enhance worker productivity, THEREFORE exposure to natural light has a positive effect on job satisfaction.
> BECAUSE exposure to natural light has a positive effect on job satisfaction, THEREFORE, the new space will enhance worker productivity. ** makes more sense.
Common argument types
In October, a local news station completed a redesign of its website. In November, the number of articles read on the website increased by 50%. Thus, the redesigned website clearly attracted more users or encouraged users to read more articles per visit.
Anticipate WHAT IFS
Causation
Conclusion: Last sentence –> The redesigned website is the CAUSE for the 50% increase in readership.
Premises:
- Oct - redesign complete
- Nov - readership increase
Anticipate WHAT IF Q’s (do you believe the author’s conclusion?)
- what if there are OTHER CAUSES for the increase?
Test by:
> removing cause and observing whether the effect is the same
Strengthen by:
> Providing more evidence in support of causation
> Providing evidence that reverse causation is not true
Weaken by:
> Providing evidence of OTHER CAUSES or reverse causation
Common argument types
Metropolis has experienced an increase in the amount of trash in its city parks. In order to reduce the amount of litter in the parks, Metropolis plans to double the number of trash cans in each city park.
Anticipate WHAT IFS
Plan
Conclusion: “In order to reduce the amount of litter in the parks” –> GOAL of a plan
(Amount of litter in the park will reduce).
Background: Statement of Fact
- Increase in the amount of trash in city parks
Premise: (Why there will be a reduction in the amount of litter in the parks?)
- Double the number of trash cans in each city park.
Anticipate WHAT IF Q’s (do you believe the author’s conclusion?)
- What if the plan doesn’t work (e.g., missed steps, unexpected hindrances?)
Common argument types
Rainfall totals were higher this year than they were last year in Eastown. Since wheat farmers rely on rain to irrigate their fields, yields of wheat per acre in Eastown will be higher than last year’s yields.
Anticipate WHAT IFS
Prediction (future tense conclusion)
Conclusion: Yields of wheat per acre will be higher than last year’s yields in Eastown.
Premise:
- Rainfall totals were higher this year than they were last year in Eastown
- Wheat farmers rely on rain to irrigate their fields
Anticipate WHAT IF Q’s (do you believe the author’s conclusion?)
- What if the author missed other factors/circumstances that might work against the prediction? (e.g., temperature)
Parts of an argument exercise:
The average level of physical fitness among students at North High School is likely to decline over the next few years. Due to recent changes in the way that the school calculates students’ grades, earning a high grade in a physical education class will no longer improve a student’ s grade point average. Therefore, students who would otherwise have taken optional gym classes will be more likely to choose other electives in which earning a high grade is worth more points.
Conclusion: “The average level of physical fitness among students at North High School is likely to decline over the next few years.”
Premises:
- Due to recent changes in the way that the school calculates students’ grades, earning a high grade in a physical education class will no longer improve a student’ s grade point average.
Intermediate Conclusion:
“Therefore, students who would otherwise have taken optional gym classes will be more likely to choose other electives in which earning a high grade is worth more points.”
THEREFORE TEST:
(1) BECAUSE the average physical fitness level among students is likely to decline, THEREFORE, students will be more likely to choose other non-gym electives to earn a high grade (WRONG)
(2) BECAUSE students will be more likely to choose other non-gym electives to earn a high grade, THEREFORE the average physical fitness level among students is likely to decline.
Parts of an argument exercise:
During the past 30 years, the percentage of the population that smokes cigarettes has consistently declined. During the same time period, however, the number of lung cancer deaths attributed to smoking cigarettes has increased.
Two premises - no conclusion!
What is meant by the following:
“The first is a finding that has been used to support a conclusion that the argument rejects”
Finding supports something that OPPOSES the argument –> counterpremise.
What are common assumptions for Plan arguments
Assumptions that validate every step of the plan will work as expected OR EXCLUDE other factors
What are common assumptions for Prediction arguments
Assumptions that no other future events beyond those mentioned in the argument will intervene.
Strengthen prediction by addressing past challenges (e.g., high cost)
Trap answers for finding the assumption questions
- No tie to the conclusion –> remember, the correct assumption must be true to make the conclusion sound –> if the assumption doesn’t tell you anything about whether the conclusion is true or not, then it is wrong.
**Don’t add your own assumptions - Irrelevant comparison or distinction
- Reverse logic - answer is the OPPOSITE of what you are looking for (b/c it weakens the argument)
Student Advisor: One of our exchange students faced multiple arguments with her parents over the course of the past year. Not surprisingly, her GPA over the same period showed a steep decline. This is just one example of a general truth: Problematic family relationships can cause significant academic difficulties for our students.
Which of the following is required for the student advisor to conclude that problematic family relationships can cause academic difficulties?
A) last year, the exchange student reduced the amount of time spent on academic work, resulting in a lower GPA
B) The decline in the GPA of the exchange student was not the reason for the student’s arguments with her parents.
C) School GPA is an accurate measure of the student’s intellectual ability
D) the student’s GPA is lower than the average GPA for exchange students at the university.
E) Fluctuations in academic performance are typical for many students.
B
- Assumption denying reverse causation
Answer is NOT D – irrelevant distinction
> It isn’t necessary to compare the student’s GPA to others in order to explain WHY her GPA decreased.
Answer is NOT A - Reverse Logic –> suggests a DIFFERENT REASON for the decline in GPA.
CAUSE-EFFECT relationship (ASSUMPTION!!!!!!!!!)
What type of error is this?
Students who earn A and B grades are more likely to participate in sports than are students who earn C grades. Therefore, participation in sports helps students achieve higher grades.
Find the Assumption
- Students who earn A grades participate in sports more frequently than those who earn B grades.
Assumption should support why participation in sports will help C students achieve higher grades.
The assumption is wrong because it is an IRRELEVANT DISTINCTION between A students and B students
> does not matter about the frequency of participation in sports
> also does not matter about the differences between A and B students (they are grouped together).
Strengthen and Weaken the argument question markers and types of answer choices
“If true” or “if feasible” or “effectively achieved” or “successfully accomplished”
Ans choices will typically be:
- Info that strengthens the argument
- Info that weakens the argument
- Info that does nothing to the argument
Strategy for Strengthen the Argument question - what should the correct ans be?
The correct ans should be RELATED TO THE CONCLUSION
e.g., Which of the following, if true, most strengthens the prediction that Donut Chain’s promotion will increase the new store’s profitability?
> Need evidence that upfront cost of attracting new customers will generate greater new business
e.g., the vast majority of new visitors to its stores become regular customers
What are Fill in the Blank question formats?
- They are a different way of presenting the existing question types (e.g., Strengthen the argument, Find the Assumption, or Inference)
“Which of the following most logically COMPLETES the argument below?”
> “since/because” ____ –> Strengthen the argument
“[If some claim is true], it should be expected that” ____ —> Inference (must be true given the info in the argument)
“[In order for some claim to be true], it must be shown that” ____ —> Inference (must be true given the info in the argument)
“[Something is true] assuming that” _____ —> Find the Assumption
The national infrastructure for airport runways and air traffic control requires immediate expansion to accommodate the increase in smaller private planes. To help fund this expansion, the Federal Aviation Authority has proposed a fee for all air travelers. However, this fee would be unfair, as it would impose costs on all travelers to benefit only the few who utilize the new private planes.
Which of the following, if true, would cast the most doubt on the claim that the proposed fee would be unfair?
(A) The existing national airport infrastructure benefits all air travelers
(B) The expansion would reduce the # of delayed flights resulting from small private planes congesting runways
(C) The fee, if imposed, will have a negligible impact on the overall volume of air travel
Weaken the Arg question
B –> this is a benefit to all passengers, which would make it more fair
A is wrong –> “existing” infrastructure doesn’t affect the conclusion at all! (no tie to conclusion trap)
EXCEPT question format
- can show up for Strengthen the Arg or Weaken the Arg (or other question types)
Remember, EXCEPT questions are just a different format of the same material studied!
e.g., “Each of the following, if true, weakens the conclusion, EXCEPT” —> right ans DOES NOT weaken the arg (i.e., strengthen OR does nothing!)
Strategy: Choose the ODD ONE OUT
e.g., Label W, S, Neither
Which of the following best completes the passage below?
A nonprofit organization in Motor City has proposed that local college students be given the option to buy half-price monthly passes for the city’s public transportation system. The nonprofit claims that this plan will reduce air pollution in Motor City while increasing profits for the city’s public transportation system. However, this plan is unlikely to meet its goals, since ___
A) Most college students in Motor City view public transportation as unsafe
B) College students typically do not have the 9-to-5 schedules of most workers, and can thus be expected to ride public transportation at times when there are plenty of empty seats
C) A bus produces more air pollution per mile than does a car
Strengthen the Arg (that offering half-price monthly passes to local college students will NOT reduce air pollution and increase profits)
> Conclusion is “however, this plan is unlikely to meet its goals, since __”
A) Related to conclusion (college students in Motor City, public transportation) –> says that even with the reduced price, most college students won’t use it. CORRECT
B) Sound related to conclusion - says that college students in GENERAL will ride at non-peak times –> may not reduce pollution? What’s the alternative? Vague
> also students would be filing what are currently empty seats (increase profits!)
C) Doesn’t talk about college students in Motor City – trying to say that even if there are more bus riders, air pollution might not go down.
> also, the plan isn’t about increasing the number of buses; it is about putting more people on already-running buses!
Traditionally, public school instructors have been compensated according to seniority. Recently, education experts have criticized the system as one that rewards lackadaisical teaching and reduces motivation to excel. Instead, these experts argue that, to retain exceptional teachers and maintain quality instruction, teachers should receive salaries or bonuses based on performance rather than seniority.
Which of the following, if true, most weakens the argument of the education experts?
A) Some teachers express than financial compensation is not the only factor contributing to job satisfaction and teaching performance
B) A merit-based system that bases compensation on teacher performance reduces collaboration, which is an integral component of quality instruction
Weaken
A - sounds right BUT there are problems
> “Some teachers” does not mean the teachers are right nor does it mean they they represent the majority
> Financial compensation is STILL a factor.
B is right
Advertising Executive: More than 10M households now own digital video recorders that can fast-forward over television commercials; approximately 75% of these households fast-forward over at least one commercial per 30-minute program. Because television commercials are not as widely watched as they used to be, they are much less cost-effective today.
Which of the following is required in order for the advertising executive to claim that television commercials are less cost-effective today?
A) Product placement within TV programs is a viable alternative to traditional tv commercials
B) The television programs preferred by consumers without digital video recorders are similar to those preferred by consumers with the devices
C) Prior to the advent of digital video recorders, very few television viewers switched channels or left the room when commercials began
D) The cost-effectiveness of television advertising is based less upon how many people watch a particular commercial and more upon the appropriateness of the demographic.
E) The amount that television channels charge for advertisers to air commercials on their channel has increased steadily over the last decade
Find the Assumption Q
A - not relevant to evaluating cost-effectiveness of traditional TV commercials
B - not relevant to evaluating cost-effectiveness of traditional TV commercials (just saying the the viewers prefer the same kinds of PROGRAMS, no even ads)
C - CORRECT - Before, people didn’t skip commercials as often, so before tv commercials generated more views, which is the goal of ads.
> Note how the premise said “because tv commercials are not as widely watched as they used to be…”
D) Reverse logic - arg is about view times
E) SEEMS CORRECT BUT ISN’T - while it is costlier to air TV commercials now, if they can get views, they can still be considered cost-effective. This statement isn’t a necessary assumption that has to be true for the argument to make sense (not widely watched as they used to be).
How to identify Evidence-based family questions (Inference and Explain a Discrepancy)?
Typically the arguments do not contain any conclusion or assumptions (just premises).
Two types of questions:
(1) Inferences - What MUST BE TRUE according to the premises.
> In the GMAT world, inferences are BULLETPROOF LOGICAL CONSEQUENCES
> If the statement is sometimes true, sometimes not true, then it isn’t correct (e.g., economists could recommend higher or the same levels of gov’t spending; OTHER causes of something)
> Often contain some variation of the words “Conclude” or “Infer”
(2) Explain a discrepancy - find an answer that EXPLAINS/RESOLVE/FIXES the puzzling part of the argument (aka, the information now makes sense together)
> Majority include “if true”
> e.g., explain why doctors no longer recommend something (like a bad reason)
How do you tell Inference questions apart from Strengthen questions?
Strengthen questions: Ans BELOW supports conclusion ABOVE (below-above, upward arrow)
Inference questions: Argument ABOVE supports correct answer BELOW (above-below, downward arrow)
> Inference arguments do not contain a conclusion (opinion) at all; just premises.
Imagine two ice cream companies, X and Y. Chocolate ice cream represents 60% of X’s sales and 50% of Y’s sales. Can we infer that Company X sells more chocolate ice cream than Company Y?
NO –> be ware of percents and actuals
Company Y could have a much higher dollar value of sales. So a smaller percentage represents a larger quantity than X!
In a recent poll, 71 percent of respondents reported that they cast votes in the most recent national election. Voting records show, however, that only 60 percent of eligible voters actually voted in that election.
Which if the following pieces, if true, would provide the best explanation for the discrepancy?
A) The margin of error for the survey was plus or minus 5 percentage points.
B) Fifteen percent of the survey’s respondents were living overseas at the time of the election.
C) Prior research has shown that people who actually do vote are also more likely to respond to polls than those who do not vote.
D) Some people who intend to vote are prevented from doing so by last-minute conflicts or other complications.
E) People are less likely to respond to a voting poll on the same day that they voted.
Explain the Discrepancy - why would the % of respondents who voted be higher than the actual % of eligible voters who voted?
C –> response bias. The subset has more people who voted in the election than the general population.
A is wrong –> 71 +/- 5 > 60
B is wrong –> Could have voted electronically or something. And why would they lie in the poll?
D is WRONG –> Discusses people who INTEND to vote, rather than explain what happened AFTER the election.
> survey is conducted AFTER the election
E is wrong –> opposite answer and not helpful.
The average fuel efficiency of vehicles sold nationwide during the period 2000-2004 was 25 miles per gallon; the corresponding figure during the period 1995-1999 was 20 miles per gallon. The national average price of gasoline during the period 2000-2004 was $2 per gallon; the corresponding figure during the period 1995-1999 was $1.60 per gallon.
The statements above, if true, best supports which of the following conclusions?
A) The average fuel efficiency of vehicles sold nationwide should reach 30 miles per gallon for the period 2005-2009.
B) The cost of gasoline for an average trip in a vehicle was higher during the period 1995-1999 than during the period 2000-2004
C) Rising gasoline prices lead consumers to purchase more fuel-efficient cars
D) The ratio of average fuel efficiency to average price of gasoline was roughly equal in the two periods
E) Consumers spent more money on gasoline during the period 1995-1999
Inference - which of the following conclusions MUST BE TRUE.
A - not necessarily true (‘should’)
B - not necessarily true / unknown length of average trip in each year. Cost of Gas = price of gas * distance
= ($/g)(g/m)m
C - TRAP answer (real world answer) - there’s no info about why consumers purchase more fuel-efficient cars (not necessarily based on rising gasoline prices).
D - TRUE
1995-1999 Avg FE to Avg P: 20/1.6 = 200/16 = 50/4 = 12.5
2000-2004 Avg FE to Avg P: 25/2 = 50/4 = 12.5
E - Not necessarily true / unknown (while price per gallon was lower, we don’t know the average trip length).
Medical education in the United States has focused almost exclusively on curative medicine, while preventive care has been given scant attention. This is misguided. Medical schools should invest as much time in teaching their students how to prevent illness as in teaching them how to cure it.
Which of the following, if true, most strengthens the argument above?
A) Many contagious diseases can be prevented with vaccines.
(B) In 1988, for every three cents the United States spent on prevention, it spent 97 cents on curative treatment.
(C) The number of students enrolled in medical school is the highest it has ever been.
(D) More people die each year from disease than from accidental causes.
(E) As the population grows, the number of doctors in certain specialties has not been keeping pace.
Strengthen
Conclusion - Medical education is misguided and should focus on both preventative and curative medicine
A is correct –> benefits of preventative medicine (vaccines) is that it can prevent many contagious diseases.
(B) is WRONG - This statement supports the idea that the more time and money are spent on curative medicine than on preventive medicine. However, it does not speak to the BENEFITS of preventive medicine.
A recent study demonstrated that parents living with children consume nearly five more grams of fat per day, on average, than do adults living without children. The higher fat intake among these parents is probably attributable to their snacking on the pizza and cookies that tend to be plentiful in households with children.
Which of the following, if true, would most seriously weaken this explanation of the parents’ higher fat intake?
A. On average, households with children spend $15 more per week on pizza and cookies than do households without children.
B. Households with children purchase much more whole milk, which has a high fat content, than do households without children.
C. Children consume most of the pizza and cookies in any given household.
D. Parents ought to set a good example for their children, in dietary choices as in other matters.
E. Not all parents living with children consume more grams of fat than do adults living without children.
Weaken the argument
Looking for an alternative reason for why parents with children have higher fat intake other than pizza and cookies.
B is correct –> whole milk
Not C - remainder of cookies and pizza could be consumed by parents. No evidence about whether adults eat more pizza and cookies than they would if no children were present.
When a company refuses to allow other companies to produce patented technology, the consumer invariably loses. The company that holds the patent can charge exorbitant prices because there is no direct competition. When the patent expires, other companies are free to manufacture the technology and prices fall. Companies should therefore allow other manufacturers to license patented technology.
The argument above presupposes which of the following?
A) Companies cannot find legal ways to produce technology similar to patented technology.
(B) Companies have an obligation to act in the best interest of the consumer.
(C) Too many patents are granted to companies that are unwilling to share them.
(D) The consumer can tell the difference between patented technology and inferior imitations.
(E) Consumers care more about price than about quality.
Find the assumption
Looking for an assumption of why companies should be allowed to use patented tech and why they should care about consumers (and whether they win or lose)
B is right –> assumption that companies should act in the best interest of consumers
E is WRONG -> even thought consumers seem to be price conscious, you could have consumers that care about quality over price and the argument would still hold. Untrue Assumptions do not make the conclusion make sense.
> Also does not address companies at all.
Some animals, such as dolphins, dogs, and African grey parrots, seem to exhibit cognitive functions typically associated with higher-order primates such as chimpanzees, gorillas, and humans. Some parrots, for example, have vocabularies of hundreds of words that they can string together in a comprehensible syntax. This clearly shows that humans and primates are not the only animals capable of using language to communicate. One parrot, named Alex, has been known to ask to be petted or kissed and will exhibit aggression if the gesture offered is not the specific one requested.
Which of the following, if true, would most strengthen the conclusion above?
A. Dolphins can be trained to assist divers in ocean rescues.
B. Gorillas in captivity often learn hand signals for food and water.
C. Dogs are capable of sensing their owners’ moods and often exhibit concern if they sense sadness.
D. Chimpanzees can memorize long sequences of key punches on machines that dispense food.
E. Alex does not exhibit aggression when offered a gesture that he specifically requested.
Strengthen
Conclusion - there are animals OTHER THAN humans and primates (chimps, gorillas) that can USE LANGUATE TO COMMUNICATE.
Exclude all the answer choices that discuss primates (B and D).
A is wrong -> does not provide evidence of communication between dolphins and humans.
C is wrong –> sensing moods and exhibiting concern is not quite communication using language.
E is correct –> demonstrates that the parrot can UNDERSTAND the DIFFERENCE between the gestures that he requests and those that he does not. In other words, he is a non-primate / non-human but he is communicating via language. IF he ALSO exhibited aggression when offered the gestures he requested, it would be more difficult to claim that he was communicating via language.
Consumer advocates argue that the coating found on non-stick cookware contains harmful chemicals that are released into the air when the cookware is heated above a certain temperature. The manufacturer of the cookware acknowledges this hazard but assures consumers that the temperature threshold is much higher than would ever be needed for food preparation and therefore no special precautions need be taken in using the cookware.
Which of the following, if true, would cast the most serious doubt on the claims of the manufacturer?
A. The chemicals released by the coating can linger in the air for days
B. Empty cookware left on the flame often reaches exceptionally high temperatures.
C. Several consumers have already claimed illness as a result of using the cookware.
D. The manufacturer did not test the cookware for this phenomenon until consumer advocates brought the issue to its attention.
E. There are effective non-stick coatings that do not release toxins when heated.
Weaken Conclusion
B - shows that there are scenarios IN FOOD PREPARATION when the cookware would reach exceptionally high temperatures
C is WRONG - there could be OTHER CAUSES for the illnesses (such as food poisoning).
Inorganic pesticides remain active on the surfaces of fruits and vegetables for several days after spraying, while organic pesticides dissipate within a few hours after application, leaving the surface of the sprayed produce free of pesticide residue. Therefore, when purchasing from a farm that uses inorganic pesticides, one must be careful to wash the produce thoroughly before eating it to prevent the ingestion of toxins. But one need not worry about ingesting pesticides when purchasing from farms that use only organic pesticides.
The argument above assumes that
(A) Consumers are aware of the origins of the produce they purchase.
(B) Produce from farms that use organic pesticides reaches the consumer within hours after it is picked or harvested.
(C) No farm uses both organic and inorganic pesticides.
(D) No pesticide is capable of penetrating the skin of a fruit or vegetable.
(E) The use of either type of pesticide does not increase the cost of produce.
Find the Assumption
D - try negation technique
> If pesticides could penetrate the skin of fruits/vegetables, then people still should be concerned about ingesting pesticides of organic produce (weakens the conclusion)
Not C
> if some farms uses both organic and inorganic pesticides, the conclusion can still be true/STILL BE VALID (pertains only to farms that use only org pesticides).
> Don’t get stuck up on the exact wording here (“purchasing FROM A FARM”)
> Also the last sentence says “purchasing from farms that use ONLY organic pesticides” –> not really an assumption here, it is a claim
Company X manufactures swim wear and planned to launch a new line of women’s bathing suits in March, which is typically the peak time of year for swim wear sales. The company conducted consumer polls, which returned favorable results for both style and price, and took out advertisements in major fashion magazines and television stations. Yet the launch was disappointing: sales in March did not exceed even half of the company’s sales during the same period in the previous year.
Each of the following, if true, could explain the disappointing sales of the new swim wear line EXCEPT:
A. None of the stores carrying the new swim wear line displayed it prominently.
B. The company’s manufacturing plants experienced difficulty in obtaining dyes in the advertised colors and so substituted different colors.
C. A major competitor launched a line of similar swim wear at a lower price in February.
D. A scene in which a major actress was to wear one of the new swimsuits in a much anticipated movie to be released in February was never filmed.
E. The prediction of a cool, rainy summer by meteorologists received much attention in the national media.
Explain the Discrepancy
> Despite launching swim wear during PEAK TIME with FAVORABLE Consumer polls (style and price) AND ADS in magazines and TV, the launch was very disappointing
> Why?
Between B and D
> B could be a reason to explain the discrepancy –> the ads contained different colours so the polls are inaccurate now
> D is correct –> REGARDLESS of when the movie was to be released, the things above should have still resulted in high sales.
All other answers are possible reasons why demand for swim suits in general is low (competition, cool summer, not shown properly).
Normally it takes a week for a cake to become moldy in a refrigerator. The cake in Alex’s refrigerator is moldy. Therefore, the cake in Alex’s refrigerator must be at least a week old.
Which of the following, if true, strengthens the conclusion?
A. Alex’s refrigerator has not been cleaned in two years.
B. A blown fuse in Alex’s building has deprived his refrigerator of electricity for the past five days.
C. The cake had just been baked when it was placed in Alex’s refrigerator; it has remained there ever since.
D. A recent study demonstrated that 95% of refrigerators currently in use will keep a cake fresh for one week.
E. The cake was baked on a Tuesday.
Strengthen the conclusion (that the cake in his fridge must be at least a week old)
Correct ans is C - gets rid of any possibility that the cake was removed out of the fridge at some point.
NOT D –> still 5% chance Alex’s fridge won’t keep the cake fresh.
The public often protests when an unregulated service industry is found to be corrupt. However, regulation often leads to increased costs for the consumer. Fewer companies survive in a regulated market, leading to decreased competition and higher prices. The public then responds negatively to the increased costs of these services.
The statements above best support which of the following
A. Service industries should not be regulated.
B. The public should not protest unregulated services.
C. Only unregulated services are subject to public protest.
D. The public is sometimes the cause of its own complaints.
E. Decreased competition always leads to increased prices
Inference –> conclusion
Public protests successfully, but then suffers and “responds negatively”
D is correct –> the public’s complaint in this situation is now the cost of services is too high in regulated markets, which was the product of what they protested for. So the public is sometimes the CAUSE of its OWN COMPLAINTS.
> A cycle of public discontent
B is incorrect –> if they did not protest unregulated services, then what do we do about the corruption? The premises don’t lead to this conclusion logically.
Is the removal of corruption a better outcome than higher prices for consumers? Or is it not?
> There is no evidence that increased costs are less desirable than corruption.
Lyme disease is caused by a bacterium transmitted to humans by deer ticks. Generally, deer ticks pick up the bacterium while in the larval stage by feeding on infected white-footed mice. However, certain other species on which the larvae feed do not harbor the bacterium. If the population of these other species were increased, more of the larvae would be feeding on uninfected hosts, so the number of ticks acquiring the bacterium would likely decline.
Which of the following would it be most important to ascertain in evaluating the argument?
A Whether populations of the other species on which deer tick larvae feed are found only in areas also inhabited by white-footed mice
B Whether the size of the deer tick population is currently limited by the availability of animals for the tick’s larval stage to feed on
C Whether the infected deer tick population could be controlled by increasing the number of animals that prey on white-footed mice
D Whether deer ticks that were not infected as larvae can become infected as adults by feeding on deer on which infected deer ticks have fed
E Whether the other species on which deer tick larvae feed harbor any other bacteria that ticks transmit to humans
Evaluate the Argument
- What ADDITIONAL info is helpful to determine whether the assumption/argument is VALID or INVALID –> info would EITHER strengthen or weaken that argument (2 paths)
B is correct
Conclusion - increasing other species would reduce diseased ticks.
First get rid of answer choices that aren’t related to larvae stage (C, D)
Second, think about the paths
B -
> If Yes, this means the deer tick pop is limited by the amount of food available. So if we increase # of uninfected hosts, deer tick pop would increase with more unaffected ticks –> strengthen conclusion
> If no, this means deer tick pop has plenty of food. So if we increase # of uninfected hosts, there’s no guarantee deer ticks would feed on other species and increase the uninfected tick population –> weaken
e.g., 1000 starting population with only white-footed mice to feed on. If we bring in 1000 other mice and they aren’t constrained, there is no guarantee # of ticks feeding on the white-footed mice would decrease.
NOT E (not related to lyme disease bacterium)
Radio stations with radio data system (RDS) technology broadcast special program information that only radios with an RDS feature can receive. Between 1994 and 1996, the number of RDS radio stations in Verdland increased from 250 to 600. However, since the number of RDS-equipped radios in Verdland was about the same in 1996 as in 1994, the number of Verdlanders receiving the special program information probably did not increase significantly.
Which of the following is an assumption on which the argument depends?
A Few if any of the RDS radio stations that began broadcasting in Verdland after 1994 broadcast to people with RDS-equipped radios living in areas not previously reached by RDS stations.
C
In 1996 Verdlanders who did not own radios equipped to receive RDS could not receive any programming from the RDS radio stations that began broadcasting in Verdland after 1994.
Find the assumption (MUST be true to make the conclusion true)
Conclusion - # of ppl receiving special program did not increase a lot
> assumes that # of listeners of special program = # of special Radios = all had access to special program
> no cases of ppl who HAD special radios but formerly could not listen to the special programs (i.e., out of reach)
A is correct
- If false - it would mean many RDS stations reached people who had special radios not previously reached before => increase # of listeners = weaken conclusion
C is incorrect –> discusses “any programming” rather than the special program information
> not a necessary assumption
In countries where automobile insurance includes compensation for whiplash injuries sustained in automobile accidents, reports of having suffered such injuries are twice as frequent as they are in countries where whiplash is not covered. Some commentators have argued, correctly, that since [there is presently no objective test for whiplash], spurious reports of whiplash injuries cannot be readily identified. These commentators are, however, wrong to draw the further conclusion that [in the countries with the higher rates of reported whiplash injuries, half of the reported cases are spurious]: clearly, in countries where automobile insurance does not include compensation for whiplash, people often have little incentive to report whiplash injuries that they actually have suffered.
In the argument given, the two boldfaced portions play which of the following roles?
A The first is evidence that has been used to support a conclusion that the argument criticizes; the second is that conclusion.
B The first is evidence that has been used to support a conclusion that the argument criticizes; the second is the position that the argument defends.
First boldface is COUNTERPREMISE
Second boldface is ALSO COUNTER –> counterconclusion
> read the FULL sentence from start to finish “wrong to draw the further CONCLUSION that___”
A is correct
According to a study of more than 50,000 Norwegian smokers, smokers who reduced their nicotine intake from cigarettes, even by up to 50 percent, did not achieve significant health benefits. The mortality rate for those who cut back on cigarettes was not lower than that for heavier smokers; moreover, the rate of cardiovascular disease was similar across all subsets of smokers in the study. As a result, the sponsors of the study claim that reducing nicotine intake does not improve one’s health.
Which of the following, if true, most seriously jeopardizes the findings of the study described above?
(A) The majority of study participants minimized their nicotine withdrawal symptoms through the use of skin patches and chewing gum that provide nicotine to the body.
(B) Many of the study’s participants periodically dined in restaurants in which smoking was permitted.
(C) The study’s participants started smoking at different ages and had varied initial nicotine intake.
(D) Quitting smoking entirely results in a marked reduction in the ill effects of smoking.
(E) Men and women who smoked pipes and cigars were excluded from the study.
Weaken the Conclusion
Conclusion - “reducing nicotine intake does NOT improve one’s health”
Ans should (1) show that reducing nicotine intake IMPROVES one’s health or (2) Study participants DID NOT actually reduce nicotine intake even if they cut back on smoking
A - CORRECT –> shows that the majority of participants did NOT reduce nicotine intake
B is INCORRECT –> while the participants likely inhale nicotine from second hand smoke, the RELATIVE change was still a reduction!
> Before study –> smoked + inhaled second hand smoke
> During study –> no smoke + inhaled second hand smoke
> Overall = experienced lower nicotine intake!
The downturn in the economy last year has prompted many companies to make widely publicized layoffs, resulting in thousands of lost jobs. Economists predicted that these layoffs would cause people generally to cut back on their discretionary spending, even if their jobs were secure, in anticipation of coming hard times. However, this prediction has not come to pass, since there has been no increase in the amount of money set aside by the general public in savings accounts.
Which one of the following is an assumption on which the argument depends?
A - the economy has not improved in recent months
B - There has been no increase in the amount of money invested in stocks, certificates of deposit, or other savings vehicles.
C - Salaries have decreased as a result of the economic downturn.
D - No business sectors have seen growth in recent months.
E - Those who were laid off have been able to find other employment.
Find the Assumption - make the conclusion true
> Last year - economic downturn caused many layoffs
Prediction - layoffs would cause increased savings due to hard times ahead
However - prediction was wrong because there was NO increased in savings by general public (savings account) - Conclusion –> therefore, there has been no cutbacks on dis purchases
Assumption - savings account is a measure of disc spending (higher dis spending, smaller savings; lower dis spending, higher savings)
> no other savings instruments to store wealth (e.g., real estate, financial assets)
A - WRONG –> state of the economy has no impact on whether savings accounts is a proxy for discretionary spending.
B - CORRECT –> offers ALTERNATIVE savings account
C - Not relevant to the amount of savings relative to before
D - same thing as A
E - you can still save if you are employed or unemployed
The downturn in the economy last year has prompted many companies to make widely publicized layoffs, resulting in thousands of lost jobs. Economists predicted that these layoffs would cause people generally to cut back on their discretionary spending, even if their jobs were secure, in anticipation of coming hard times. However, this prediction has not come to pass, since there has been no increase in the amount of money set aside by the general public in savings accounts.
The answer to which of the following questions would be most useful in evaluating the significance of the savings patterns described above?
(A) What business sectors were most affected by the layoffs?
(B) How much of their savings, on average, do laid-off employees deplete before finding new employment?
(C) What has been the percent increase in the cost of necessities such as food, housing, and utilities during the period since the layoffs?
(D) What percentage of people laid off have savings accounts?
(E) What has been the average salary during the period since the layoffs?
Evaluate the Argument - two paths (strengthen and weaken the conclusion)
–> asked to evaluate the SIGNIFICANCE of the savings patterns using which of the following questions
i.e., are the savings patterns something we should be concerned about?
–> Pattern: No increase in the amount of $ in savings accounts ==> what does this signify? (lower, same, or higher discretionary spending?)
A - x - irrelevant to look at which business sectors were affected –> should be broader POV
B - x - prediction applies to general population (those who have been laid off or have jobs)
C - if cost of necessities has increased a ton => explains why savings reduced –> weaken arg that dis spending increased.
if cost of necessities has not increased a ton => reduced savings is more likely to be caused by dis purchases –> strengthen arg
ANS
D - x - prediction applies to general population
E - x - irrelevant to consider salary –> someone with a high salary might save less than someone with lower salary
e.g., High salary after layoffs –> more likely to spend ? But could also save
Low salary after layoffs –> don’t know what happens to saving versus spending
Candidate for Mayor: My opponent argues that the best way to increase the city’s tax revenues is to double the tax on rental cars so that non-residents provide the bulk of the additional income. This plan is unethical because it constitutes taxation without representation: we should not excessively tax those who cannot vote on the plan. Moreover, if car rental prices are too high in our city, people may simply rent cars in neighboring cities to avoid the tax surcharge.
The candidate responds to her opponent’s plan by ______.
A) Introducing a moral quandary that cannot be resolved without additional data.
B) Arguing for an alternate strategy by which to accomplish the declared objective.
C) Claiming that the opponent’s proposal contains inaccurate data.
D) Implying that the plan may result in the opposite of the intended effect.
E) Demonstrating that her opponent’s plan would fail to achieve its goal.
Describe the Argument
Opponent’s plan: Tax non-residents to increase tax revenues
Candidate responds by claiming the plan is
1) Unethical –> but could work
2) Lead to unintended results –> non-residents would not rent in the city => likely lead to reduced tax revenues
A) “Moral” sounds nice BUT what additional data do we need to resolve it?
> Does the response indicate a moral “quandary” or dilemma?
> The candidate simply states it is unethical
B) No alternate strategy was proposed –> the candidate attacks the premises and conclusion (plan will increase tax revenues)
C) No mention of questioning the opponent’s data
D) True - “imply” or “suggest”
E) WRONG
> It is true that the candidate offers a REASON why the plan might not work as intended (would cause people to avoid tax surcharge = reduce tax revenues = the goal of the plan)
> BUT the candidate does not “demonstrate” or “prove” that the plan would 100% fail
Every year many people become ill because of airborne mold spores in their homes. After someone becomes ill, specialists are often hired to eradicate the mold. These specialists look in damp areas of the house, since mold is almost always found in places where there is substantial moisture. To minimize the risk of mold poisoning in the home, then, one should make sure to keep all internal plumbing in good condition to prevent leakage that could serve as a breeding ground for mold.
Which of the following is an assumption on which the argument depends?
A) Mold itself does not create moisture.
B) Most homeowners know enough about plumbing to determine whether theirs is in good condition.
C) Mold cannot grow in dry areas.
D) No varieties of mold are harmless.
E) Mold spores cannot be filtered from the air.
Assumption
“mold is almost always found in places where there is substantial moisture” –> implies that moistures CAUSES mold
Conclusion - preventing leakages via plumbing problems will minimize the risk of mold poisoning (again, relying on minimizing moisture)
A) If the REVERSE CAUSATION were true, then keeping all plumbing in good condition might not minimize mold growth
C) is WRONG. The argument says only that mold is almost always found in web places and that preventing leaks would minimize mold poisoning. The argument DOES NOT rely on the idea that it is IMPOSSIBLE for mold to grow in dry areas.
D) is WRONG. (D) The argument does not rely on the idea that every variety of mold is harmful; it merely discusses what to do to AVOID poisoning from THOSE types of mold that are harmful.
> if we have harmless mold –> still can minimize RISK of mold poisoning
E) is not related to the conclusion (potential for mold growth via plumbing leaks).
However, Wynne-Edwards’ theory, linking animal social behavior and population control, has been challenged, with some justification, by several studies
The challenge posed to the Wynne-Edwards-theory by several studies is regarded by the author with:
A) Complete Indifference
B) Qualified acceptance
B –> Qualified acceptance means that the author accepted the challenge, but modified it (with “some”)
There is no evidence of “complete” indifference.
Jay: Of course there are many good reasons to support the expansion of preventive medical care, but arguments claiming that it will lead to greater societal economic gains are misguided. Some of the greatest societal expenses arise from frequent urgent-care needs for people who have attained a long life due to preventive care.
Sunil: Your argument fails because you neglect economic gains outside the health care system: society suffers an economic loss when any of its productive members suffer preventable illnesses.
Sunil’s response to Jay makes which of the following assumptions:
A Those who receive preventive care are not more likely to need urgent care than are those who do not receive preventive care.
B. Jay intends the phrase “economic gains” to refer only to gains accruing to institutions within the health care system.
C. Productive members of society are more likely than others to suffer preventable illnesses.
D. The economic contributions of those who receive preventive medical care may outweigh the economic losses caused by preventive care.
E. Jay is incorrect in stating that patients who receive preventive medical care are long-lived.
Describe the Argument
Sunil claims that Jay’s argument is flawed because he ignored economic gains from avoiding productivity losses
> Sunil concludes that preventive medical care can lead to greater societal economic gains
> So she assumes that the avoided productivity losses > additional societal expenses.
D
Half of Metroburg’s operating budget comes from a payroll tax of 2 percent on salaries paid to people who work in the city. Recently a financial services company, one of Metroburg’s largest private-sector employers, announced that it will be relocating just outside the city. All the company’s employees, amounting to 1 percent of all people now employed in Metroburg, will be employed at the new location.
From the information given, which of the following can most properly be concluded?
A. Unless other employers add a substantial number of jobs in Metroburg, the company’s relocation is likely to result in a 1 percent reduction in the revenue for the city’s operating budget.
B. Although the company’s relocation will have a negative effect on the city’s tax revenue, the company’s departure will not lead to any increase in the unemployment rate among city residents.
C. One of the benefits that the company will realize from its relocation is a reduction in the taxes paid by itself and its employees.
D. Revenue from the payroll tax will decline by 1 percent if there is no increase in jobs within the city to compensate, fully or partially, for the company’s departure.
E. The company’s relocation will tend to increase the proportion of jobs in Metroburg that are in the public sector, unless it results in a contraction of the public-sector payroll.
Inference - MUST BE TRUE
> If 1% of people who are employed in the city leave the city, we DON’T KNOW the impact of the move on TAXES (e.g., we have no information about the salaries of these people).
So eliminate all answer choices that predict 1% reduction in revenues (A, D).
C is obviously wrong (cannot guarantee the next location won’t have higher taxes)
B is wrong –> we have no information about the downstream effects of the move (e.g., could increase unemployment in other businesses)
E is correct –> we know that 1% of all employees that are relocating are private sector employees.
Urban rail systems have been proposed to alleviate traffic congestion, but results in many cities have been cited as evidence that this approach to traffic management is ineffective. For example, a U.S. city that opened three urban rail branches experienced a net decline of 3,100 urban rail commuters during a period when employment increased by 96,000. Officials who favor urban rail systems as a solution to traffic congestion have attempted to counter this argument by noting that commuting trips in that city represent just 20 percent of urban travel.
What is the officials’ claim?
Commuters make up only 20% of urban travel. So even if there was a decline in rail usage by commuters, traffic congestion will not increase if 80% of noncommuters use the rail.
ASSUMPTION - commuters and noncommuters contribute equally to traffic congestion
In order to reduce dependence on imported oil, the government of Jalica has imposed minimum fuel-efficiency requirements on all new cars, beginning this year. The more fuel-efficient a car, the less pollution it produces per mile driven. As Jalicans replace their old cars with cars that meet the new requirements, annual pollution from car traffic is likely to decrease in Jalica.
Which of the following, if true, most seriously weakens the argument?
C. Some pollution-control devices mandated in Jalica make cars less fuel-efficient than they would be without those devices.
D. Jalicans who get cars that are more fuel-efficient tend to do more driving than before.
Conclusion: Annual POLLUTION from CAR TRAFFIC is likely to DECREASE (more fuel efficient cars)
WEAKEN
(evidence that annual poll from car traffic won’t decrease)
D is correct - if they drive more often, could be emitting more pollution overall
C is wrong - some devices that have been mandated make cars less fuel-efficient than before. This would not decrease pollution.
> however, NEW FUEL-EFFICIENCY standards may STILL IMPROVE their avg fuel efficiency and reduce air pollution
> Error: Confused about the meaning of this answer (all new cars have new min fuel efficiency standards, though the fuel efficiency might be curbed. However, compared to before these min requirements, fuel efficiency is still better!)
To improve customer relations, several big retailers have recently launched “smile initiatives,” requiring their employees to smile whenever they have contact with customers. These retailers generally have low employee morale, which is why they have to enforce smiling. However, studies show that customers can tell fake smiles from genuine smiles and that fake smiles prompt negative feelings in customers. So the smile initiatives are unlikely to achieve their goal.
The argument relies on which of the following as an assumption?
A. The smile initiatives have achieved nearly complete success in getting employees to smile while they are around customers.
B. Customers’ feelings about fake smiles are no better than their feelings about the other facial expressions employees with low morale are likely to have.
C. The feelings that employees generate in retail customers are a principal determinant of the amount of money customers will spend at a retailer.
D. At the retailers who have launched the smile initiatives, none of the employees gave genuine smiles to customers before the initiatives were launched.
E. Customers rarely, if ever, have a negative reaction to a genuine smile from a retail employee.
Find the Assumption
C: smile initiative is unlikely to improve cust. relations (b/c fake smiles prompt negative feelings)
Assumption - negative feelings are the same as those prompted by employees with low morals
Ans: B
Harvester-ant colonies live for fifteen to twenty years, though individual worker ants live only a year. The way a colony behaves changes steadily in a predictable pattern as the colony grows older and larger. For the first few years, the foragers behave quite aggressively, searching out and vigorously defending new food sources, but once a colony has reached a certain size, its foragers become considerably less aggressive.
If the statements above are true, which of the following can most properly be concluded on the basis of them?
A. As a result of pressure from neighbors, some colonies do not grow larger as they become older.
B. Unpredictable changes in a colony’s environment can cause changes in the tasks that the colony must perform if it is to continue to survive.
C. The reason a mature colony goes out of existence is that younger, more aggressive colonies successfully outcompete it for food.
D. The pattern of changing behavior that a colony displays does not arise from a change in the behavior of any individual worker ant or group of worker ants.
E. A new colony comes into existence when a group of young, aggressive workers leaves a mature colony and sets up on its own.
Inference - MUST ALWAYS BE TRUE
D - clearly the any colonies act in COORDINATED WAYS (they ALL start off quite aggressive and then become less aggressive). So the behaviour of colonies is NOT because of any one ant.
NOT C - we cannot say for certain that the REASON a mature colony goes out of existence is because of the reason cited.
Which of the following most logically completes the argument?
A photograph of the night sky was taken with the camera shutter open for an extended period. The normal motion of stars across the sky caused the images of the stars in the photograph to appear as streaks. However, one bright spot was not streaked. Even if the spot were caused, as astronomers believe, by a celestial object, that object could still have been moving across the sky during the time the shutter was open, since __________.
A. the spot was not the brightest object in the photograph
B. the photograph contains many streaks that astronomers can identify as caused by noncelestial objects
C. stars in the night sky do not appear to shift position relative to each other
D. the spot could have been caused by an object that emitted a flash that lasted for only a fraction of the time that the camera shutter was open
E. if the camera shutter had not been open for an extended period, it would have recorded substantially fewer celestial objects
Strengthen
Conclusion - the object could have still been moving across the sky, despite having produced no streaks
NOT C
> The object could have been a celestial object, which is NOT a star
> We care about the positions relative to THE CAMERA
> If the other stars are shifting position, then then this object (if it is a star) should have also moved.
D is correct
> The object could have been moving without emitting a light.
Codex Berinensis, a Florentine copy of an ancient Roman medical treatise , is undated but contains clues to when it was produced. Its first 80 pages are by a single copyist, but the remaining 20 pages are by three different copyists, which indicates some significant disruption. Since a letter in handwriting identified as that of the fourth copyist mentions a plague that killed many people in Florence in 1148, Codex Berinensis was probably produced in that year.
Which of the following, if true, most strongly supports the hypothesis that Codex Berinensis was produced in 1148?
(A) Other than Codex Berinensis, there are no known samples of the handwriting of the first three copyists.
(B) According to the account by the fourth copyist, the plague went on for 10 months.
(C) A scribe would be able to copy a page of text the size and style of Codex Berinensis in a day.
(D) There was only one outbreak of plague in Florence in the 1100s.
(E) The number of pages of Codex Berinensis produced by a single scribe becomes smaller with each successive change of copyist.
Strengthen (causal - plague of 1148 delayed the production of Codex)
C: Codex was probably produced in 1148
> due to SIGNIFICANT DISRUPTION
D is correct
> The fourth copyist would live at most to 1200, so 1100s is the correct time frame to think about
> If there was only one outbreak of plague in Florence in 1100s, then the fourth copyist was alive during the plague in 1148.
> Strengthens that Codex was produced in 1148
HOWEVER I am concerned that the fourth copyist could have taken a looong time to copy it… (1148 versus 1149?)
B is incorrect
> what if the fourth copyist is talking about a different plague than the one in 1148?
C is incorrect
> took the last three copyists 20 days to complete Codex
> while it is proof that Codex could be produced in under a year, but it does not help us determine THE EXACT YEAR.
Overall, we care about evidence that tells us WHEN Codex was produced.
In an attempt to reduce the crime rate, the governor is getting tough on criminals and making prison conditions harsher. Part of this effort has been to deny inmates the access they formerly had to college-level courses. However, this action is clearly counter to the governor’s ultimate goal, since after being released from prison, inmates who had taken such courses committed far fewer crimes overall than other inmates.
Which of the following is an assumption on which the argument depends?
A) Not being able to take college-level courses while in prison is unlikely to deter anyone from a crime that he or she might otherwise have committed.
(B) Former inmates are no more likely to commit crimes than are members of the general population.
(C) The group of inmates who chose to take college-level courses were not already less likely than other inmates to commit crimes after being released.
(D) Taking high school level courses in prison has less effect on an inmate’s subsequent behavior than taking college-level courses does.
(E) The governor’s ultimate goal actually is to gain popularity by convincing people that something effective is being done about crime.
Find the Assumption
C is correct
> try negation technique (which should break down the conclusion)
> The group of inmates who chose to take courses were ALREADY LESS LIKELY than others to commit crimes after being released
> So if the governor denies them access, crime rate would be unchanged for this group
> Regardless of access to these courses, crime rate among these inmates would be the same
> For other inmates, the harsher conditions in general COULD reduce crime rate => breaks down the conclusion that the plan won’t work
The assumption is the the inmates who took college-level courses were THE SAME REGULAR INMATE and therefore could benefit from taking courses
NOT A
> States that the threat won’t work to reduce crime rate = no effect
> Conclusion is that the threat counters the governor’s ultimate goal = increases crime rate
> Negation is: Not being able to take course would LIKELY DETER some people from committing crimes
> But if it is not the MAJORITY of people, then the conclusion would not break down.
“If both of these sources are accurate, however, there is an error in stating that __________.”
What type of question is this?
Inference - look for an answer that MUST BE WRONG
> eliminate answers that could be true
Technological improvements and reduced equipment costs have made converting solar energy directly into electricity far more cost-efficient in the last decade. However, the threshold of economic viability for solar power (that is, the price per barrel to which oil would have to rise in order for new solar power plants to be more economical than new oil-fired power plants) is unchanged at thirty-five dollars.
Which of the following, if true, does most to help explain why the increased cost-efficiency of solar power has not decreased its threshold of economic viability?
(A) The cost of oil has fallen dramatically.
(B) The reduction in the cost of solar-power equipment has occurred despite increased raw material costs for that equipment.
(C) Technological changes have increased the efficiency of oil-fired power plants.
(D) Most electricity is generated by coal-fired or nuclear, rather than oil-fired, power plants.
(E) When the price of oil increases, reserves of oil not previously worth exploiting become economically viable
Ans: C
A is wrong because the THRESHOLD (35 dollars) is UNAFFECTED by changes in the cost of oil
If efficiency of converting solar energy into electricity has increased, then the efficiency of oil-fired power plants must also increase in order for the threshold of economic viability to remain unchanged
Comcorp Shipping Clerk: Last week, no shipments of building supplies were sent out on Friday. The five specially ordered shipments sent out last week were sent out on Thursday, and each of those specially ordered shipments consisted entirely of building supplies. Four shipments were sent to Truax Construction last week, none of which consisted of building supplies. If the shipping clerk’s statements are true, which of the following must also be true?
(A) All of Comcorp’s shipments of building supplies last week were specially ordered.
(B) None of Comcorp’s shipments sent on Friday of last week was sent to Truax Construction.
(C) None of the shipments sent by Comcorp to Truax Construction last week was specially ordered.
(D) None of Comcorp’s shipments sent on Thursday of last week was sent to Truax Construction.
(E) All of Comcorp’s shipments of building supplies last week were sent out on Thursday.
Ans: C
“The five specially ordered shipments sent out last week were sent out on Thursday” – ALL of the specially ordered shipments were building supplies
THEREFORE, since the shipments sent to Truax were NOT building supplies, they CANNOT BE SPECIALLY ORDERED.
Twenty years ago, Balzania put in place regulations requiring operators of surface mines to pay for the reclamation of mined-out land. Since then, reclamation technology has not improved. Yet, the average reclamation cost for a surface coal mine being reclaimed today is only four dollars per ton of coal that the mine produced, less than half what it cost to reclaim surface mines in the years immediately after the regulations took effect.
Which of the following, if true, most helps to account for the drop in reclamation costs described?
(A) Even after Balzania began requiring surface mine operators to pay reclamation costs, coal mines in Balzania continued to be less expensive to operate than coal mines in almost any other country.
(B) In the twenty years since the regulations took effect, the use of coal as a fuel has declined from the level it was at in the previous twenty years.
(C) Mine operators have generally ceased surface mining in the mountainous areas of Balzania because reclamation costs per ton of coal produced are particularly high for mines in such areas.
(D) Even after Balzania began requiring surface mine operators to pay reclamation costs, surface mines continued to produce coal at a lower total cost than underground mines.
(E) As compared to twenty years ago, a greater percentage of the coal mined in Balzania today comes from surface mines.
Explain the discrepancy
Discrepancy - even though reclamation tech has not improved from 20 years ago, the AVERAGE reclamation cost for a surface coal mine today is LOWER than the reclamation cost immediately after the regulations took effect
> what might explain why the average cost is lower?
C is the answer –. stopped surface mining in an area that had high reclamation cost
NOT B –> reclamation cost is unaffected by use of the coal.
Yeasts capable of leavening bread are widespread, and in the many centuries during which the ancient Egyptians made only unleavened bread, such yeasts must frequently have been mixed into bread doughs accidentally. The Egyptians, however, did not discover leavened bread until about 3000 B.C. That discovery roughly coincided with the introduction of a wheat variety that was preferable to previous varieties because its edible kernel could be removed from the husk without first toasting the grain.
Which of the following, if true, provides the strongest evidence that the two developments were causally related?
(A) Even after the ancient Egyptians discovered leavened bread and the techniques for reliably producing it were well known, unleavened bread continued to be widely consumed.
(B) Only when the Egyptians stopped the practice of toasting grain were their stone-lined grain-toasting pits available for baking bread.
(C) Heating a wheat kernel destroys its gluten, a protein that must be present in order for yeast to leaven bread dough.
(D) The new variety of wheat, which had a more delicate flavor because it was not toasted, was reserved for the consumption of high officials when it first began to be grown.
(E) Because the husk of the new variety of wheat was more easily removed, flour made from it required less effort to produce.
Strengthen
> Development #1) Discovery of leavened bread
Development #2) Introduction of non-toasted wheat variety
C is the answer
> By using non-toasted wheat that does not require first heating the wheat kernel, yeast can now leaven bread dough because there is GLUTEN
B is wrong
> Even though the Egyptians could bake bread following development #2, it does not mean that it caused the discovery of leavened bread
> The bread could have been unleavened bread
Which of the following most logically completes the passage? Each species of moth has an optimal body temperature for effective flight, and when air temperatures fall much below that temperature, the moths typically have to remain inactive on vegetation for extended periods, leaving them highly vulnerable to predators. In general, larger moths can fly faster than smaller ones and hence have a better chance of evading flying predators, but they also have higher optimal body temperatures, which explains why-___________.
(A) large moths are generally able to maneuver better in flight than smaller moths
(B) large moths are proportionally much more common in warm climates than in cool climates
(C) small moths are more likely than large moths to be effectively camouflaged while on vegetation
(D) large moths typically have wings that are larger in proportion to their body size than smaller moths do
(E) most predators of moths prey not only on several different species of moth but also on various species of other insects
Inference
The key phrase is “optimal body temperature for effective flight”, below which the moths cannot fly.
If larger moths have higher optimal body temperatures, they are likely to be found in WARMER climates. Otherwise, these larger moths would have to remain inactive for extended periods of time.
If they had lower optimal body temperatures, they can survive in cooler climates (i.e., still be able to fly)
Surveys in Domorica indicate that only 10 percent of Domoricans in their twenties read a newspaper regularly, while more than half of all Domoricans over thirty read a newspaper regularly. Although Domoricans in their twenties constitute a large proportion of the population, newspaper publishers nonetheless predict that ten years from now, the percentage of Domoricans who regularly read a newspaper will probably be no lower than it is today.
Which of the following, if true, provides the strongest grounds for the newspaper publishers’ prediction?
(A) The number of Domoricans in their twenties is less than the number of Domoricans over thirty.
(B) The number of newspapers in Domorica has been gradually increasing over the past several decades.
(C) The proportion of Domoricans in their twenties who regularly read a newspaper has always been low.
(D) The surveys defined a regular reader of a newspaper as someone who reads a newspaper more than twice a week.
(E) The proportion of Domoricans who regularly read a newspaper was higher 20 years ago than it is today.
Strengthen
Conclusion - % of Domoricans who regularly read a newspaper will not be lower than it is today
Pre-thinking: Because people read more as they age
Ans: C –> says that readership among people in their twenties has always been low, even for the population aged 30+ right now
NOT A:
> In ten years, the people who were twenty now would become 30+
> If readership % were maintained and assume some people over 30 died/stopped reading, readership would LOWER
> We also only care about PERCENTAGE of readership rather than # of readers
Most of the world’s supply of uranium currently comes from mines. It is possible to extract uranium from seawater, but the cost of doing so is greater than the price that uranium fetches on the world market. Therefore, until the cost of extracting uranium from seawater can somehow be reduced, this method of obtaining uranium is unlikely to be commercially viable.
Which of the following would it be most useful to determine in evaluating the argument?
(A) Whether the uranium in deposits on land is rapidly being depleted
(B) Whether most uranium is used near where it is mined
(C) Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater
(D) Whether the total amount of uranium in seawater is significantly greater than the total amount of uranium on land
(E) Whether uranium can be extracted from freshwater at a cost similar to the cost of extracting it from seawater
Evaluate the argument
Ans: A
> If land uranium deposits are quickly being depleted, then the PRICE of uranium on the world market is likely to INCREASE
> With the cost of extracting uranium from seawater remaining constant, the method can now be considered commercially viable (conclusion is false - we don’t need to wait until the cost of extracting is reduced)
> Otherwise if land uranium deposits are not being quickly depleted, the conclusion is true
NOT C
> A “promise” is still speculative and is not helpful in evaluating the conclusion (“Until the cost of extracting uranium from seawater can somehow be reduced”)
Which of the following most logically completes the argument? United States manufacturers currently produce most of the world’s solar-power generators–most of which are exported to Europe. However, European manufacturers are emerging and probably will ultimately capture much of the European market. The United States government is funding initiatives intended to encourage use of solar power within the United States. If these initiatives succeed in increasing the demand for solar-power generators in the United States, United States manufacturers will probably maintain significant production levels, since __________.
(A) some United States manufacturers have been substantially increasing their output over the last several years
(B) the efficiency of solar-power generators in converting energy from the Sun into electric power is not improving as fast as it once did
(C) just as European manufacturers enjoy certain competitive advantages in Europe, so do United States manufacturers in the United States
(D) European governments are currently undertaking initiatives to stimulate the use of solar power within Europe
(E) the current market for solar-power generators in the United States is very limited
Strengthen
Ans: C
> the author has assumed that the increased demand of solar power generators will be fulfilled by supplies of US manufacturers AND NOT FOREIGN MANUFACTURERS
> thus, US manufacturers are likely to continue to produce at high levels
NOT E
> we already know demand for solar-power generators in the US is currently very low
Finding of a survey of Systems magazine subscribers: Thirty percent of all merchandise orders placed by subscribers in response to advertisements in the magazine last year were placed by subscribers under age thirty-five. Finding of a survey of advertisers in Systems magazine: Most of the merchandise orders placed in response to advertisements in Systems last year were placed by people under age thirty-five.
For both of the findings to be accurate, which of the following must be true?
(A) More subscribers to Systems who have never ordered merchandise in response to advertisements in the magazine are age thirty-five or over than are under age thirty-five.
(B) Among subscribers to Systems, the proportion who are under age thirty-five was considerably lower last year than it is now.
(C) Most merchandise orders placed in response to advertisements in Systems last year were placed by Systems subscribers over age thirty-five.
(D) Last year, the average dollar amount of merchandise orders placed was less for subscribers under age thirty-five than for those age thirty-five or over.
(E) Last year many people who placed orders for merchandise in response to advertisements in Systems were not subscribers to the magazine.
Assumption question with Percents
E is correct
Looking at JUST SUBSCRIBERS: 30% orders placed by ppl under 35 years old and majority (70%) placed by ppl older than 35 years old.
However, looking at the TOTAL ORDERS PLACED (include subscribers and non-subscribers): Majority placed by ppl under 35 years old.
The only way for both to be true is if there were MORE NON-SUBSCRIBERS who placed orders
