Question
The speed of a boat in still water is twice the speed of
the current. If the boat takes 10 hours to cover 150 km upstream, then find the time taken by the boat to cover 300 km downstream.Solution
Let the speed of the current be ‘x’ km/hr
Therefore, speed of the boat in still water = 2x km/hr
According to the question,
2x – x = 150 / 10
Or, x = 15 km/hr
Required time taken = 300 / (2x + x) = 300 / (3 × 15) = 300/45 = 6 hours
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