Question
The speed of a boat in still water is 8 km/hr more than
that of the current. The time taken by the boat to travel 288 km downstream and 96 km upstream, together is 24 hours. Find the speed of the boat in still water.Solution
Let the speed of the current be ‘x’ km/hr
Therefore, speed of the boat in still water = (x + 8) km/hr
According to the question,
{288/(x + x + 8)} + (96/8) = 24
Or, 288/(2x + 8) + 12 = 24
Or, 288/(2x + 8) = 12
Or, 2x + 8 = 288/12 = 24
Or, 2x = 24 − 8 = 16
Or, x = 16/2 = 8
Therefore, speed of the boat in still water = x + 8 = 16 km/hr
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