Question
A boat moving upstream takes 8 hours 48 minutes to cover
a distance while it takes 4 hours to return to the starting point, downstream. What is the ratio of the speed of boat in still water to that of water current?Solution
Let the speed of the boat be x km/h And the speed of the stream be y km/h Distance travel in Upstream is = (x - y) × 8(4/5)  = (x - y) × 44/5 Distance travel in Downstream is= (x + y) × 4 Since the distance is the same – (x - y) x 44/5 = (x + y) x 4 11x - 11y = 5x + 5y  6x = 16y  x/y = 8/3 x: y=8:3
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