GMAT Quantitative: Algebraic Word Problems 2

Question 1

A train travels 240 miles at a constant speed. If the speed had been 20 mph faster, the trip would have taken 1 hour less. What was the original speed?

Accepted Answer

40 mph

Answer

240/x − 240/(x+20) = 1 gives x² + 20x − 4800 = 0, so x = 40.

Question 2

The sum of two numbers is 30 and their difference is 8. What is the larger number?

Accepted Answer

19

Answer

Adding the equations gives 2x = 38, so the larger number is 19.

Question 3

A number increased by 25% equals 80. What is the number?

Accepted Answer

64

Answer

1.25x = 80, so x = 64.

Question 4

Tom is twice as old as Jerry. In 6 years, the sum of their ages will be 42. How old is Tom now?

Accepted Answer

20

Answer

2x + 6 + x + 6 = 42 gives x = 10, so Tom is 20.

Question 5

A rectangle's length is 3 more than twice its width. If the perimeter is 36, what is the width?

Accepted Answer

5

Answer

2(2w+3) + 2w = 36 gives 6w = 30, so w = 5.

GMAT Practice Test

GMAT Practice Test

GMAT Quantitative: Algebraic Word Problems 2