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.

In a certain business, production index p is directly proportional to efficiency index e, which is in turn directly proportional to investment i. What is p if i = 70?

In a certain business, production index p is directly proportional to efficiency index e, which is in turn directly proportional to investment i. What is p if i = 70? (1) e = 0.5 whenever i = 60 (2) p = 2.0 whenever i = 50 A. Statement (1) ALONE is sufficient, but statement (2) […]

In a certain business, production index p is directly proportional to efficiency index e, which is in turn directly proportional to investment i. What is p if i = 70? Read the Full Article »

The product of two negative numbers is 160. If the lesser of the two numbers is 4 less than twice the greater, what is the greater number?

The product of two negative numbers is 160. If the lesser of the two numbers is 4 less than twice the greater, what is the greater number? (A) -20 (B) -16 (C) -10 (D) -8 (E) -4 Correct Answer: D Full explanation coming soon. Send us a note if you’d like this added to the

The product of two negative numbers is 160. If the lesser of the two numbers is 4 less than twice the greater, what is the greater number? Read the Full Article »

The present ratio of students to teachers at a certain school is 30 to 1. If the student enrollment were to increase by 50 students and the number of teachers were to increase by 5, the ratio of students to teachers would then be 25 to 1. What is the present number of teachers?

The present ratio of students to teachers at a certain school is 30 to 1. If the student enrollment were to increase by 50 students and the number of teachers were to increase by 5, the ratio of students to teachers would then be 25 to 1. What is the present number of teachers? (A)

The present ratio of students to teachers at a certain school is 30 to 1. If the student enrollment were to increase by 50 students and the number of teachers were to increase by 5, the ratio of students to teachers would then be 25 to 1. What is the present number of teachers? Read the Full Article »