GMAT Question of the Day – Problem Solving – Work

Tank A contains X gallons of water while Tank B contains Y gallons. Tank A has water removed at a rate of K gallons per hour and Tank B has water added at a rate of M gallons per hour. Assuming that both tanks still contain some water, in terms of X, Y, K, and M how many gallons of water will both tanks have 2 minutes from now?

A.  (x – y – m + k)/60

B. (30(x-y) – m + k)/60

C. (30(x-y) + m – k)/60

D. (30(x-y) + m – k)/30

E. (30(x-y) – m + k)/30

[spoiler]D.[/spoiler]

GMAT Question of the Day Solution

For GMAT work and rate questions it helps to organize the information in T’s. This way you have a place to store the numbers in a way that identifies what the numbers represent. The T’s also help you make inferences. Notice that in this question there is a unit conversion from minutes to hours. For GMAT work and rate questions it’s a great idea to double check the units before committing to an answer.