Calculate the speed of a boat in still water (in km/hr) if in one hour, the boat goes 10 km/hr downstream and 4 km/hr upstream.\nOptions:\n(A) 7 kmph\n(B) 8 kmph\n(C) 9 kmph\n(D) 7 kmph\n(E) 6 kmph
Let's be accurate as possible. Think before you answer.
(A)
Speed in still water = (10 + 4)1/2 kmph = 7 kmph.

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Therefore, the answer is (A)