MathDB
2006 Algebra #1: Swimming Through Cambridge

Source:

July 30, 2012
HarvardcollegeMIT

Problem Statement

Larry can swim from Harvard to MIT (with the current of the Charles River) in 4040 minutes, or back (against the current) in 4545 minutes. How long does it take him to row from Harvard to MIT, if he rows the return trip in 1515 minutes? (Assume that the speed of the current and Larry’s swimming and rowing speeds relative to the current are all constant.) Express your answer in the format mm:ss.