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.

A researcher plans to identify each participant in a certain medical experiment with a code consisting of either a single letter or a pair of distinct letters written in alphabetical order. What is the least number of letters that can be used if there are 12 participants, and each participant is to receive a different code?

A researcher plans to identify each participant in a certain medical experiment with a code consisting of either a single letter or a pair of distinct letters written in alphabetical order. What is the least number of letters that can be used if there are 12 participants, and each participant is to receive a different […]

A researcher plans to identify each participant in a certain medical experiment with a code consisting of either a single letter or a pair of distinct letters written in alphabetical order. What is the least number of letters that can be used if there are 12 participants, and each participant is to receive a different code? Read the Full Article »

If Q is an odd number and the median of Q consecutive integers is 120, what is the largest of these integers?

If Q is an odd number and the median of Q consecutive integers is 120, what is the largest of these integers? A. (Q-1)/2+120 B. Q/2+119 C. Q/2+120 D. (Q+119)/2 E. (Q+120)/2 Correct Answer: A Full explanation coming soon. Send us a note if you’d like this added to the express queue! You’ll find tons

If Q is an odd number and the median of Q consecutive integers is 120, what is the largest of these integers? Read the Full Article »

A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d?

A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d? A. 16% B. 32% C. 48% D. 84% E. 92% Correct Answer:

A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m + d? Read the Full Article »

In the first week of the year, Nancy saved $1. In each of the next 51 weeks, she saved $1 more than she had saved in the previous week. What was the total amount that Nancy saved during the 52 weeks?

In the first week of the year, Nancy saved $1. In each of the next 51 weeks, she saved $1 more than she had saved in the previous week. What was the total amount that Nancy saved during the 52 weeks? A. $1,326 B. $1,352 C. $1,378 D. $2,652 E. $2,756 Correct Answer: C Full explanation

In the first week of the year, Nancy saved $1. In each of the next 51 weeks, she saved $1 more than she had saved in the previous week. What was the total amount that Nancy saved during the 52 weeks? Read the Full Article »

In a box of 12 pens, a total of 3 are defective. If a customer buys 2 pens selected at random from the box, what is the probability that neither pen will be defective?

In a box of 12 pens, a total of 3 are defective. If a customer buys 2 pens selected at random from the box, what is the probability that neither pen will be defective? A. 1/6 B. 2/9 C. 6/11 D. 9/16 E. 3/4 Correct Answer: C Full explanation coming soon. Send us a note

In a box of 12 pens, a total of 3 are defective. If a customer buys 2 pens selected at random from the box, what is the probability that neither pen will be defective? Read the Full Article »