Question
A boat can travel 8 km more in downstream than that in
upstream, in 8 hours while the difference between the time taken by the same boat to travel 200 km and 126 km, in still water, is 4 hours. Find the approximate time taken by the boat to travel 267 km in downstream and 173 km in upstream.Solution
Stream speed y=0.5 km/h (from distance difference in 8 hours) So: Downstream speed = 18.5+0.5=19 km/h Upstream speed = 18.5−0.5=18 km/h Now calculate time:
Total time = 14.05 + 9.61 = 23.7 hours or 24 hours (approx)
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