Q: A man rows his boat 105 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?\nOptions:\n(A) 5 kmph\n(B) 7 kmph\n(C) 12 kmph\n(D) 8 kmph\n(E) 1 kmph Let's give some random thoughts before answering.
User
Speed downstream = d/t = 105/(2 1/2) = 42 kmph\nSpeed upstream = d/t = 45/(2 1/2) = 18 kmph\nThe speed of the stream = (42 - 18)/2 = 12 kmph
Therefore, the answer is (C).
Assistant