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.

If the relations shown hold for the operation ⊕ and the numbers m, n, p, q, and r, then [(m⊕p)⊕q]⊕p=

m⊕p=n n⊕r=m n⊕q=q p⊕q=p q⊕p=r If the relations shown hold for the operation ⊕ and the numbers m, n, p, q, and r, then [(m⊕p)⊕q]⊕p= A. m B. n C. p D. q E. r Correct Answer: E Full explanation coming soon. Send us a note if you’d like this added to the express queue! You’ll find tons of […]

If the relations shown hold for the operation ⊕ and the numbers m, n, p, q, and r, then [(m⊕p)⊕q]⊕p= Read the Full Article »

If xy ≠ 0 and x²y² − xy = 6, which of the following could be y in terms of x?

If xy ≠ 0 and x2y2 − xy = 6, which of the following could be y in terms of x? I.1/2x II.-(2/x) III.3/x A. I only B. II only C. I and II D. I and III E. II and III Correct Answer: E Full explanation coming soon. Send us a note if you’d like this added to the express queue! You’ll

If xy ≠ 0 and x²y² − xy = 6, which of the following could be y in terms of x? Read the Full Article »

According to a certain estimate, the depth N(t), in centimeters, of the water in a certain tank at t hours past 2:00 in the morning is given by N(t) = −20(t − 5)²+ 500 for 0 ≤ t ≤ 10. According to this estimate, at what time in the morning does the depth of the water in the tank reach its maximum?

According to a certain estimate, the depth N(t), in centimeters, of the water in a certain tank at t hours past 2:00 in the morning is given by N(t) = −20(t − 5)2 + 500 for 0 ≤ t ≤ 10. According to this estimate, at what time in the morning does the depth of the water in the tank reach its maximum? A.

According to a certain estimate, the depth N(t), in centimeters, of the water in a certain tank at t hours past 2:00 in the morning is given by N(t) = −20(t − 5)²+ 500 for 0 ≤ t ≤ 10. According to this estimate, at what time in the morning does the depth of the water in the tank reach its maximum? Read the Full Article »

The cost C, in dollars, to remove p percent of a certain pollutant from a pond is estimated by using the formula C=100,000p/(100−p). According to this estimate, how much more would it cost to remove 90 percent of the pollutant from the pond than it would cost to remove 80 percent of the pollutant?

The cost C, in dollars, to remove p percent of a certain pollutant from a pond is estimated by using the formula C=100,000p/(100−p). According to this estimate, how much more would it cost to remove 90 percent of the pollutant from the pond than it would cost to remove 80 percent of the pollutant? A. $500,000 B. $100,000 C.

The cost C, in dollars, to remove p percent of a certain pollutant from a pond is estimated by using the formula C=100,000p/(100−p). According to this estimate, how much more would it cost to remove 90 percent of the pollutant from the pond than it would cost to remove 80 percent of the pollutant? Read the Full Article »