Answer to GMAT Question #13

Here is the answer to GMAT Practice Question #13

Answer: C

Explanation:
In order for k/m(squared) to be an integer, k must cancel with m twice. For example, if m is 5, then k must be a number such as 75, which cancels with 5 twice. Another way to say this is that k must be a multiple of m(squared).

We can quickly eliminate A, B, and D as possible answers, because Statement 1 does not include m and Statement 2 does not include k. So neither give enough information to address the question.

To see if the answer is C, start with Statement 2, which says that n is divisible by m. One way to understand this is to say that n has m in it as one of its factors. Statement 1 says that k is divisible by n(squared), which must include m(squared) as a result of Statement 2. Since k is divisible by n(squared), it must also be divisible by m(squared).

You can also solve this by plugging in numbers. For example, if m is 3, n could be 6, or 9, etc. Let’s say that n is 6. Statement 1 says that k is divisible by n(squared), or 36. So k could be 72, for example. Since 72 is divisible by 9, which is m(squared), we can see that together we can solve the problem. Try plugging in one or two more numbers to be sure.

The answer and explanation to GMAT Practice Question #13 was written by Integrated Learning, a company that provides professional and private one on one tutoring services.