General Words Problems

Question 1

is

Answer 1

=

Question 2

was

Answer 2

=

Question 3

has been

Answer 3

=

Question 4

years older

Answer 4

+

Question 5

years younger

Answer 5

-

Question 6

less

Answer 6

-

Question 7

times

Answer 7

*

Question 8

fewer

Answer 8

-

Question 9

as many

Answer 9

*

Question 10

factor

Answer 10

*

Question 11

Age problems

Answer 11

In nearly all the age problems, we are presented with ages at a different point, so

1st: Define the present day using a variable
2nd: If we need to represent the age in the present-day then add that variable
3rd: If we need to represent the age in the past, we subtract from that variables

Question 12

Length Problems

Answer 12

-> typically ask us to that something has been cut into segments and we need to determine the lengths of one or more pieces

To determine it:

1st: Let each piece represent different variable
2nd: The sum of all the variables will be equal to the whole rope

Question 13

Total cost of item purchased

Answer 13

price per item * number of items

Question 14

Price per item

Answer 14

numbers of identical items purchased

Question 15

Profit

Answer 15

Total Revenue - Total Cost

-> Profit = Total Revenue - [ Total Fixed Cost + Total Variable Cost]

Question 16

Splitting the Cost

Answer 16

i.e:
if 10 poeple were to split the cost of a bill that was d dollars, the cost per person would be d/10 dollars. If only 8 people actually split the bill, those 8 people would each pay d/8 dollars, a difference of d/8- d/10= d/40

Question 17

Which salary should I choose?/ How much will I make

Answer 17

Two alternative ways to compensate for the job/ when the person would be indifferent
–> you can equal them to each others and by doing that we will yield a variable that will yield a same pay

Question 18

Which Price Structure makes the most sense/how much will I pay

Answer 18

you can make the two prices equal to each other

Question 19

Fraction Word Problems

Answer 19

i.e:
If the first friend serves himself 1/3 of the pizza and the second friend serves himself 2/3 of what remains, what fractions of the pizza will be left?
-> It would be mistake to assume that since 1/3 of the pizza was removed initially and another 2/3 was removed after that, the pizza must be gone.
-> You fail to notice that the second friend did not serve himself 2/3 of the pizza -> he served himself 2/3 of what was remained after the first amount was taken

Question 20

The fractional parts of the whole numbers must sum to the whole

Answer 20

when the whole number or whole value is broken up into fractional parts, the sum of the fractions, as well as any remaining parts, must equal the (original) whole

Question 21

Simple Interest

Answer 21

= Principalratetime

• > units for the rate must match the units of time (if the rate were expressed as 2 percent per month, the units for the time would have to be expressed in months)
• > GMAT will commonly present an annual interest rate for a loan or investment whose duration is less than a year

Question 22

When interest rate is expressed as a variable such as z percent, use

Answer 22

x/100 rather than using simple x

Question 23

Compound interest

A=

Answer 23

A= P(1+(r/n))^nt

A= future value if the investment 
P= initial value (principal) 
r= interest rate per year (expressed in decimal form) 
t= time (number of years) 
n= number of compounding periods per year

Question 24

In compounding periods when interest is paid more than once

Answer 24

we need to match the number of compounding periods

-> we do it by making adjustment to the r/n

Question 25

Linear Growth model formula

Answer 25

Fn= Kn+p where:

Fn = final value after the growth has occurred
k = growth constant
n = number of growth periods and p = original value prior to the growth

Question 26

In exponential Growth

Answer 26

initial growth value is multiplied by a constant factor in each growth period. When exponential growth occurs the amount by which the initial value increases in each growth period is not constant

Equation: (initial value) * ( growth factor) ^growth period

Question 27

In order to determine growth rate

Answer 27

• we need a growth driver
• > if we see a pattern, just don’t go a ahead and make assumption -> you need to know the growth driver
• > they need to explicitly tell you that something doubles, triples in certain time

Question 28

Exponent decay

Answer 28

When exponential decay occurs, the amount of decay decreases with each successive decay period. The greatest decay occurs during the first period of the decay

Question 29

One digit is often referred to as

Answer 29

unit digit

Question 30

Whole digit term

Answer 30

• billion
• hundred millions
• ten millions
• one millions
• hundred thousands
• ten thousand
• one thousand
• hundreds
• tens
• ones

Question 31

Decimal

Answer 31

• tenths
• hundredths
• thousandths

Question 32

The value of two digit will follow this equation

Answer 32

10(Tens digit)+unit digit = the value of any two-digit number
i.e: 48 -> 40+8

Question 33

Consecutive word problems

Answer 33

It’s helpful to let the first integer be x and add/ multiply from there

Question 34

Consecutive odd and even integer can be written as

Answer 34

x, x+2, x+4..

Question 35

Consecutive multiple can be written as

Answer 35

for multiple of 5: x, x+5, x+10, x+15

for multiple of 8: x, x+8, x+16….

Question 36

Mixture problems can be solved using a

Answer 36

matrix 
i.e 
                     Price per coin  * Number of coins  = values 
Gold Coins 
Silver Coins 
-------------------
Mixture

Question 37

Mixture of problem for drinks

Answer 37

% of apple juice Volume of drink Total apple juice
.present

10% apple juice
17% apple drink
————————

Question 38

Dry Mixture formula

Answer 38

rate*time = amount formula

Question 39

Examples of drying mixture

Answer 39

1) Price per pound * number of pounds = total price
2) Fractions of class wearing shoes * number of students in the class = total number wearing shoes
3) Interest rate on bonds * value of bonds= Total interest

Question 40

In general if you (or anyone) are the mth person counted from the beginning of the line and the nth person counted from the end of the line, then the number of people waiting in the line is

Answer 40

m+n-1

i. e:
- If you are the 10th person, counting from the beginning of the line, there are 9 people in front of you
- If you are the 15th person, counting from the end of the line, there are 14 people behind you

• > 9+1+14= 24
• > 10+15-1= 24