A man rows his boat 85 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) 9 kmph\n(D) 8 kmph\n(E) 1 kmph Let's think first. Stream of consciousness:
User
Speed downstream = d/t = 85/(2 1/2) = 34 kmph\nSpeed upstream = d/t = 45/(2 1/2) = 18 kmph\nThe speed of the stream = (34 - 18)/2 = 8 kmph
So, the answer is (D).
Assistant