Given below are two quantities named A and B. Based on the given information, you have to determine the relation between the two quantities. You should use the given data and your knowledge of Mathematics to choose between the possible answers.

Quantity A: A man goes certain distance downstream in 2 hours and returns back upstream in 3 hours. If the stream flows at the rate of 4 km/hr, find the time taken by the man to cover the distance in still water.

Quantity B: 3 hours