Read the following SAT test question and then click on a button to select your answer.

A mechanic can install carburetors in 3 cars every 4 hours. At that rate, how long will it take the mechanic to install carburetors in 5 cars?

(A) 6 hr 20 min
(B) 6 hr 40 min
(C) 7 hr 15 min
(D) 7 hr 30 min
(E) 7 hr 45 min

来源:可可英语 http://www.kekenet.com/sat/201507/388034.shtml