GMAT Forum 2025, Discuss, Learn And Practice Together

If (x − y)(x + y) = 143, and (x − y) and (x + y) are prime, what is the value of the sum of all possible values of y?

A. -1
B. 0
C. 1
D. 12
E. 24

If k is the average (arithmetic mean) of the first 8 positive multiples of 6 greater than 6, and if p is the median of the first 8 positive multiples of 6 greater than 6, what is the value of k/p ?

A. 10/11
B. 1
C. 11/10
D. 12/11
E. 0

If x is a number such that x^2−3x+2=0 and x^2−x−2=0, what is the value of x ?

(A) -2
(B) -1
(C) 0
(D) 1
(E) 2

If x^2 /4 is an integer greater than 50, and x is a positive integer, then what is the smallest possible value for x^2 ?

A. 121
B. 144
C. 169
D. 225
E. 256

If x, y, and z are positive integers and 3x = 4y = 7z, then the least possible value of x + y + z is

A. 33
B. 40
C. 49
D. 61
E. 84

An arithmetic sequence of numbers begins p, 2p + 2, 4p + 3... What is the 13th member of this sequence?

A. 37
B. 40
C. 26p + 13
D. 53
E. 129p + 13

If x is a positive integer and 4x–3=y, which of the following CANNOT be a value of y ?

A. 1
B. 7
C. 13
D. 61
E. 253

The ratio of the present ages of a father and a son is 8 : 1. Eight years from now, the ratio would be 10 : 3. What is the present age of the father?

A. 24
B. 32
C. 40
D. 48
E. 56

For how many integer values of x, is |3x−3|+|2x+8|<15 ?

A. 2
B. 3
C. 4
D. 5
E. 6

Three machines, individually, can do a certain job in 4, 5, and 6 hours, respectively. What is the greatest part of the job that can be done in one hour by two of the machines working together at their respective rates?

(A) 11/30
(B) 9/20
(C) 3/5
(D) 11/15
(E) 5/6