Question
The speed of the stream is 10 km/h. Boat βAβ covers
180 km distance against the stream in 6 hours and boat βBβ covers 90 km distance against the stream in 2 hours. The speed of boat βA in still water is how much percent of the speed of boat βBβ in still water?Solution
Speed of boat βAβ upstream = 180/6 = 30 km/h Speed of boat βBβ upstream = 90/2 = 45 km/h Speed of the boat βAβ in still water = 30 + 10 = 40 km/h Speed of the boat βBβ in still water = 45 + 10 = 55 km/h Required percentage = (40/55) Γ 100 = 72.7%
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