Question
A boat takes one-third time in moving a certain distance
downstream than upstream. The ratio of the speed of the boat in still water and that of the current isSolution
Let the speed of boat in still water = x km/hr, and Speed of current = y km/hr Rate downstream = (x + y) km/hr, and Rate upstream = (x – y) km/hr Distance = Speed × Time Řž (x - y) × 3t = (x + y) × t => 3x - 3y = x + y => 3x - x = 3y + y => 2x = 4y => x/y = 4/2 = 2 : 1
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