Gmat_mission wrote:If 90/k is an integer, is k an integer?
(1) k > 1
(2) k is a multiple of a prime number.
Given: 90/k is an integer
Target question: Is k an integer?
Statement 1: k > 1
Let's TEST some values.
There are several values of k that satisfy statement 1. Here are two:
Case a: k = 10. Notice that 90/k = 90/10 = 9, which is an integer. In this case, the answer to the target question is
YES, k IS an integer
Case b: k = 90/77. Notice that 90/k = 90/(90/77) = 90(77/90) = 77, which is an integer. In this case, the answer to the target question is
NO, k is NOT an integer
ince we cannot answer the
target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: k is a multiple of a prime number.
All prime numbers are INTEGERS, and all multiples of integers are integers.
So, the answer to the target question is
YES, k IS an integer
Since we can answer the
target question with certainty, statement 2 is SUFFICIENT
Answer: B
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
