Question
The speed of a boat while moving upstream is 20% less
than its speed in still water. The boat covers a distance of 348 km downstream in 7 hours and 15 minutes. Find the total time required for the boat to travel 104 km upstream and 270 km in still water.Solution
Let speed of boat in still water be ‘x’ km/h
Speed of boat in upstream = 0.8x km/h
Speed of boat in downstream = x + 0.2x = 1.2x km/h
So, 1.2x = 348/7.25 = 48
So, x = 40
Desired time = 104/32 + 270/40 = 3.25 + 6.75 = 10 hours
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