Question
A boat can travel 30 km upstream and 45 km downstream in
6 hours. Find the speed of the boat in still water if the speed of the stream is 4 km/h.Solution
ATQ, Let the speed of the boat in still water be ‘x’ km/h. Upstream speed = ‘x – 4’ km/h Downstream speed = ‘x + 4’ km/h According to the question: 
Thus, the speed of the boat in still water is 12 km/h .
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