Logical Reasoning Questions (Hard) Flashcards
Review LR questions that I've gotten wrong in practice tests
In the past decade, a decreasing percentage of money spent on treating disease X went to pay for standard methods of treatment, which are known to be effective though they are expensive and painful.An increasing percentage is being spent on nonstandard treatments, which cause little discomfort.Unfortunately, the nonstandard treatments have proved to be ineffective.Obviously, less money is being spent now on effective treatments of disease X than was spent ten years ago.
Which one of the following, if assumed, allows the conclusion above to be properly drawn?
A) Varieties of disease X requiring expensive special treatment have become less common during the past decade.
B) Nonstandard methods of treating disease X are more expensive now than they were a decade ago.
C) Of total medical expenditures, the percentage that is due to treatment of disease X increased during the past decade.
D) Most of the money spent on treating disease X during the last decade went to pay for nonstandard treatments.
E) The total amount of money spent on treating disease X slowly declined during the past decade
PT 102, Section 3, Question 18
E) The total amount of money spent on treating disease X slowly declined during the past decade.
Knowledge of an ancient language is essential for reading original ancient documents. Most ancient historical documents, however, have been translated into modern languages, so scholars of ancient history can read them for their research without learning ancient languages. Therefore, aspirants to careers as ancient-history scholars no longer need to take the time to learn ancient languages.
The argument is vulnerable to criticism on which one of the following grounds?
A) It concludes that something is never necessary on the grounds that it is not always necessary.
B) A statement of fact is treated as if it were merely a statement of opinion.
C) The conclusion is no more than a restatement of the evidence provided as support of that conclusion.
D) The judgment of experts is applied to a matter in which their expertise is irrelevant.
E) Some of the evidence presented in support of the conclusion is inconsistent with other evidence provided.
PT 102, Section 4, Question 8
A) It concludes that something is never necessary on the grounds that it is not always necessary.
Taken together, some 2,000 stocks recommended on a popular television show over the course of the past 12 years by the show’s guests, most of whom are successful consultants for multibillion-dollar stock portfolios, performed less successfully than the market as a whole for this 12-year period. So clearly, no one should ever follow any recommendations by these so-called experts.
Each of the following, if true, weakens the argument EXCEPT:
A) Taken together, the stocks recommended on the television show performed better than the market as a whole for the past year.
B) Taken together, the stocks recommended on the television show performed better for the past 12-year period than stock portfolios that were actually selected by any other means.
C) Performance of the stocks recommended on the television show was measured by stock dividends, whereas the performance of the market as a whole was measured by change in share value.
D) Performance of the stocks recommended on the television show was measured independently by a number of analysts, and the results of all the measurements concurred.
E) The stock portfolios for which the guests were consultants performed better for the past 12-year period than the market as a whole.
PT 102, Section 4, Question 11
D) Performance of the stocks recommended on the television show was measured independently by a number of analysts, and the results of all the measurements concurred.
The dwarf masked owl, a rare migratory bird of prey, normally makes its winter home on the Baja peninsula, where it nests in the spiny cactus. In fact, there are no other suitable nesting sites for the dwarf masked owl on the Baja peninsula. But a blight last spring destroyed all of the spiny cacti on the Baja peninsula. So unless steps are taken to reestablish the spiny cactus population, the dwarf masked owl will not make its home on the Baja peninsula this winter.
The argument depends on assuming which one of the following?
A) No birds of prey other than the dwarf masked owl nest in the spiny cactus.
B) If the Baja peninsula contains spiny cacti, then the dwarf masked owl makes its winter home there.
C) On occasion the dwarf masked owl has been known to make its winter home far from its normal migratory route.
D) The dwarf masked owl will not make its winter home on the Baja peninsula only if that region contains no spiny cacti.
E) Suitable nesting sites must be present where the dwarf masked owl makes its winter home.
PT 102, Section 4, Q25
E) Suitable nesting sites must be present where the dwarf masked owl makes its winter home.
At night, a flock of crows will generally perch close together in a small place—often a piece of wooded land—called a roost. Each morning, the crows leave the roost and fan out in small groups to hunt and scavenge the surrounding area. For most flocks, the crows’ hunting extends as far as 100 to 130 kilometers (60 to 80 miles) from the roost. Normally, a flock will continue to occupy the same roost for several consecutive years, and when it abandons a roost site for a new one, the new roost is usually less than eight kilometers (five miles) away.
Of the following claims, which one can most justifiably be rejected on the basis of the statements above?
A) Crows will abandon their roost site only in response to increases in the population of the flock.
B) When there is a shortage of food in the area in which a flock of crows normally hunts and scavenges, some members of the flock will begin to hunt and scavenge outside that area.
C) Most of the hunting and scavenging that crows do occurs more than eight kilometers (five miles) from their roost.
D) Once a flock of crows has settled on a new roost site, it is extremely difficult to force it to abandon that site for another.
E) When a flock of crows moves to a new roost site, it generally does so because the area in which it has hunted and scavenged has been depleted of food sources.
PT 102, Section 4, Question 26
E) When a flock of crows moves to a new roost site, it generally does so because the area in which it has hunted and scavenged has been depleted of food sources.
When a planetary system forms, the chances that a planet capable of supporting life will be formed are high. The chances that a large planet the size of Jupiter or Saturn will be formed, however, are low. Without Jupiter and Saturn, whose gravitational forces have prevented Earth from being frequently struck by large comets, intelligent life would never have arisen on Earth.Since planetary systems are unlikely to contain any large planets, the chances that intelligent life will emerge on a planet are, therefore, low.
Knowing which one of the following would be most useful in evaluating the argument?
A) whether all planetary systems are formed from similar amounts of matter
B) whether intelligent species would be likely to survive if a comet struck their planet
C) whether large comets could be deflected by only one large planet rather than by two
D) how high the chances are that planetary systems will contain many large comets
E) how likely it is that planetary systems containing large planets will also contain planets the size of Earth
PT 103, Section 1, Question 22
D) how high the chances are that planetary systems will contain many large comets
That wall is supported by several joists.The only thing that can have caused the bulge that the wall now has is a broken joist. Therefore, at least one of the joists is broken.
Which one of the following arguments is most similar in its logical features to the argument above?
A) At least one of the players in the orchestra must have made a mistake, since nothing else would have made the conductor grimace in the way she just did.
B) The first piece must have been the easiest, since it was the only piece in the entire concert in which the orchestra did not make many mistakes.
C) The players play well only when they like the music, since they tend to make mistakes when they play something they do not like.
D) One of the orchestra’s players must be able to play the harp, since in one of the pieces they are playing at next week’s concert the composer specified that a harp should be played.
E) The emotion of the music is the only thing that can have caused the conductor to look so angry just then, since the orchestra was playing perfectly.
PT 103, Section 1, Question 24
A) At least one of the players in the orchestra must have made a mistake, since nothing else would have made the conductor grimace in the way she just did.
Editorialist: Society is obliged to bestow the privileges of adulthood upon its members once they are mature enough to accept the corresponding responsibilities. But science has established that physiological development is completed in most persons by age seventeen. Since this maturing process has been completed by most seventeen-year-olds, there is no reason not to grant these citizens all of the privileges of adulthood.
The editorialist’s argument is most vulnerable to criticism on the ground that it
A) assumes what it is trying to prove
B) too hastily reaches a general conclusion on the basis of a few examples
C) equivocates with respect to a central concept
D) too readily accepts a claim by appeal to inappropriate authority
E) ignores the fact that some people are mature at age sixteen
PT 103, Section 2, Question 15
C) equivocates with respect to a central concept
Each child in a group of young children read aloud both a short paragraph and a list of randomly ordered words from the paragraph. The more experienced readers among them made fewer pronunciation errors in whichever task they performed second, whether it was the list or the paragraph. The order in which the two tasks were performed, however, had no effect on the performance of beginning readers, who always made fewer pronunciation errors when reading the paragraph than when reading the list.
Which one of the following, if true, most helps to explain why the order in which the tasks were performed was not significant for the beginning readers?
A) Because several words were used more than once in the paragraph but only once in the list, the list was shorter than the paragraph.
B) In reading the paragraph, the more experienced readers were better at using context to guess at difficult words than were the beginning readers.
C) The more experienced readers sounded out difficult words, while the beginning readers relied solely on context to guess at difficult words.
D) Both tasks used the same words, so that the words the children read in whichever task was performed first would be recognized in the second task.
E) The beginning readers made more pronunciation errors than the more experienced readers did in reading both the paragraph and the list.
PT 103, Section 2, Question 18
C) The more experienced readers sounded out difficult words, while the beginning readers relied solely on context to guess at difficult words.
Anthropologist: Violence is an extreme form of aggression, and is distinct from the self-expression sufficient for survival under normal conditions. Human beings in certain situations react to unpleasant stimuli with violence—but only because they are conditioned by their culture to react in this manner.
Each of the following can be logically inferred from the anthropologist’s statements EXCEPT:
A) Not all aggression is violent.
B) The self-expression required for survival is generally nonaggressive.
C) Some behaviors are influenced by the cultures in which human beings live.
D) In normal circumstances, human beings can survive by responding nonviolently.
E) Violent behavior is a product of one’s cultural environment.
PT 103, Section 2, Question 19
B) The self-expression required for survival is generally nonaggressive.
Martha’s friend, who is very knowledgeable about edible flowers, told Martha that there are no edible daisies, at least not any that are palatable. Martha, however, reasons that since there are daisies that are a kind of chrysanthemum and since there are edible chrysanthemums that are quite palatable, what her friend told her must be incorrect.
Which one of the following has a flawed pattern of reasoning most like that in Martha’s reasoning?
A) Jeanne is a member of the city chorus, and the city chorus is renowned. So Jeanne is an excellent singer.
B) Rolfe belongs to the library reading group, and all members of that group are avid readers. So Rolfe is an avid reader.
C) Some of Noriko’s sisters are on the debate team, and some members of the debate team are poor students. So at least one of Noriko’s sisters must be a poor student.
D) Most of Leon’s friends are good swimmers, and good swimmers are quite strong. So it is likely that at least some of Leon’s friends are quite strong.
E) Many of Teresa’s colleagues have written books. Most of the books they have written are on good writing. So some of Teresa’s colleagues are good writers.
PT 103, Section 2, Question 20
C) Some of Noriko’s sisters are on the debate team, and some members of the debate team are poor students. So at least one of Noriko’s sisters must be a poor student.
In a certain municipality, a judge overturned a suspect’s conviction for possession of an illegal weapon. The suspect had fled upon seeing police and subsequently discarded the illegal weapon after the police gave chase. The judge reasoned as follows: the only cause for the police giving chase was the suspect’s flight; by itself, flight from the police does not create a reasonable suspicion of a criminal act; evidence collected during an illegal chase is inadmissible; therefore, the evidence in this case was inadmissible.
Which one of the following principles, if valid, most helps to justify the judge’s decision that the evidence was inadmissible?
A) Flight from the police could create a reasonable suspicion of a criminal act as long as other significant factors are involved.
B) People can legally flee from the police only when those people are not involved in a criminal act at the time.
C) Police can legally give chase to a person only when the person’s actions have created a reasonable suspicion of a criminal act.
D) Flight from the police should not itself be considered a criminal act.
E) In all cases in which a person’s actions have created a reasonable suspicion of a criminal act, police can legally give chase to that person.
PT 103, Section 2, Question 23
C) Police can legally give chase to a person only when the person’s actions have created a reasonable suspicion of a criminal act.
Tires may be either underinflated, overinflated, or neither. We are pretty safe in assuming that underinflation or overinflation of tires harms their tread. After all, no one has been able to show that these do not harm tire tread.
Which one of the following most accurately describes a flaw in the argument’s reasoning?
A) The argument assumes what it is attempting to demonstrate.
B) The argument overlooks that what is not in principle susceptible to proof might be false.
C) The argument fails to specify how it is that underinflation or overinflation harms tire tread.
D) The argument rejects the possibility that what has not been proven is nevertheless true.
E) The argument fails to precisely define the terms “underinflation” and “overinflation.”
PT 103, Section 3, Question 10
D) The argument rejects the possibility that what has not been proven is nevertheless true.
The stable functioning of a society depends upon the relatively long-term stability of the goals of its citizens. This is clear from the fact that unless the majority of individuals have a predictable and enduring set of aspirations, it will be impossible for a legislature to craft laws that will augment the satisfaction of the citizenry, and it should be obvious that a society is stable only if its laws tend to increase the happiness of its citizens.
The claim that a society is stable only if its laws tend to increase the happiness of its citizens plays which one of the following roles in the argument?
A) It is the conclusion of the argument.
B) It helps to support the conclusion of the argument.
C) It is a claim that must be refuted if the conclusion is to be established.
D) It is a consequence of the argument.
E) It is used to illustrate the general principle that the argument presupposes.
PT 104, Section 1, Question 17
B) It helps to support the conclusion of the argument.
Research indicates that 90 percent of extreme insomniacsconsume large amounts of coffee. Since Tom drinks a lot of coffee, it is quite likely that he is an extreme insomniac.
Which one of the following most accurately describes a flaw in the argument’s reasoning?
A) It fails to acknowledge the possibility that Tom is among the 10 percent of people who drink large amounts of coffee who are not extreme insomniacs.
B) It fails to consider the possible contribution to extreme insomnia of other causes of insomnia besides coffee.
C) It relies on evidence that does not indicate the frequency of extreme insomnia among people who drink large amounts of coffee.
D) It draws an inference about one specific individual from evidence that describes only the characteristics of a class of individuals.
E) It presumes without warrant that drinking coffee always causes insomnia.
Pt 104, Section 1, Question 23
C) It relies on evidence that does not indicate the frequency of extreme insomnia among people who drink large amounts of coffee.
Researcher: The vast majority of a person’s dreams bear no resemblance whatsoever to real events that follow the dreams. Thus, it is unreasonable to believe that one has extrasensory perception solely on the basis of having had several vivid dreams about events that happen after the dreams.
Which one of the following arguments is most similar in its reasoning to the argument above?
A) It is unreasonable to believe that a new drug cures heart disease when it is tested, albeit successfully, on only a few patients. Most new drugs require testing on large numbers of patients before they are considered effective.
B) Many people who undergo surgery for ulcers show no long-term improvement. So it is unreasonable to believe that surgery for ulcers is effective, even though ulcer surgery benefits many people as well.
C) Even though many cancer patients experience remissions without drinking herbal tea, it is unreasonable to believe that not drinking herbal tea causes such remissions. Several factors are known to be relevant to cancer remission.
D) A number of people who die prematurely take aspirin. But it is unreasonable to conclude that aspirin is dangerous. Most people who take aspirin do not die prematurely.
E) A significant number of children raised near power lines develop cancer. So it is unreasonable to deny a connection between living near power lines and developing cancer, even though many people living near power lines never develop cancer.
PT 104, Section 1, Question 26
D) A number of people who die prematurely take aspirin. But it is unreasonable to conclude that aspirin is dangerous. Most people who take aspirin do not die prematurely.
