A person can row at 10 kmph and still water. He takes 5 hours to row from A to B and back. What is the distance between A and B if the speed of the stream is 2 kmph? Pick:
A) 32 km	B) 25 km	C) 28 km	D) 24 km	E) 20 km

Rationale: let the distance between a and b be x km . total time = x / ( 10 + 2 ) + x / ( 10 - 2 ) = 5 = > x / 12 + x / 8 = 5 = > ( 2 x + 3 x ) / 24 = 5 = > x = 24 km . answer : d
Answer: D