Answer to GMAT Question #16

Here is the answer to GMAT Practice Question #16

Answer: A

Explanation:
To solve this question quickly, we need to know how to sum consecutive numbers quickly.

The process, as we teach all our students, is the following:

1. Find the middle number by averaging the endpoints:

(37 + 5)/2 = 21

2. Find the number of numbers. When we are including both the first and last number, subtract the endpoints and add 1:

(37 – 5) + 1 = 33

3. Multiply:

21x33 = 693

Now find the prime factors of 693. You will see that they are 3, 3, 7, 11.

Thus, the lowest prime factor is 3.

The answer and explanation to GMAT Practice Question #16 was written by Integrated Learning, a company that provides professional and private one on one tutoring services.