Andrew Geller

Andrew Geller is a top GMAT tutor based out of New York City. Throughout his career he has successfully taught people from many different backgrounds, countries, and starting scores.

The value of (10^8-10^2)/(10^7-10^3) is closest to which of the following?

The value of (10^8-10^2)/(10^7-10^3) is closest to which of the following? A. 1 B. 10 C. 10^2 D. 10^3 E. 10^4 Correct Answer: B Full explanation coming soon. Send us a note if you’d like this added to the express queue! You’ll find tons of practice questions, explanations for GMAT Official Guide questions, and strategies […]

The value of (10^8-10^2)/(10^7-10^3) is closest to which of the following? Read the Full Article »

For every positive even integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(100) +1, then p is?

For every positive even integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(100) +1, then p is? A. Between 2 and 20 B. Between 10 and 20 C. Between 20 and 30 D. Between

For every positive even integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(100) +1, then p is? Read the Full Article »

If n and y are positive integers and 450y=n^3, which of the following must be an integer?

If n and y are positive integers and 450y=n^3, which of the following must be an integer? I. y/3∗2^2∗5 II. y/3^2∗2∗5 III. y/3∗2∗5^2 A. None. B. I only. C. II only. D. III only. E. I, II, and III Correct Answer: B Full explanation coming soon. Send us a note if you’d like this added

If n and y are positive integers and 450y=n^3, which of the following must be an integer? Read the Full Article »

Pumps A, B, and C operate at their respective constant rates. Pumps A and B, operating simultaneously, can fill a certain tank in 6/5 hours; pumps A and C, operating simultaneously, can fill the tank in 3/2 hours; and pumps B and C, operating simultaneously, can fill the tank in 2 hours. How many hours does it take pumps A, B, and C, operating simultaneously, to fill the tank.

Pumps A, B, and C operate at their respective constant rates. Pumps A and B, operating simultaneously, can fill a certain tank in 6/5 hours; pumps A and C, operating simultaneously, can fill the tank in 3/2 hours; and pumps B and C, operating simultaneously, can fill the tank in 2 hours. How many hours

Pumps A, B, and C operate at their respective constant rates. Pumps A and B, operating simultaneously, can fill a certain tank in 6/5 hours; pumps A and C, operating simultaneously, can fill the tank in 3/2 hours; and pumps B and C, operating simultaneously, can fill the tank in 2 hours. How many hours does it take pumps A, B, and C, operating simultaneously, to fill the tank. Read the Full Article »

If each term in the sum a1 + a2 + a3 +…+ an is either 7 or 77 and the sum equals 350, which of the following could be equal to n?

A. 38 B. 39 C. 40 D. 41 E. 42 Stumped by this GMAT sequence puzzle from the GMAT Prep tests 1 and 2? We’ve got you covered! We’ll do a quick overview on sequences so you have a sense for what this means: If each term in the sum a1 + a2 + a3

If each term in the sum a1 + a2 + a3 +…+ an is either 7 or 77 and the sum equals 350, which of the following could be equal to n? Read the Full Article »