Question
Speed of a boat in still water is 15 kmph and speed of
stream is 12 kmph. A man rows to a place at a distance of 54 km and come back to starting point. The total time taken by him is:Solution
ATQ, For upstream(against the stream), the effective speed is (V-S), where V is the speed of boat = 15km/h S is the speed of the styream = 12km/h downstream speed (v+s)=15+12=27km/h Upstream speed(V-S) = 15 - 12 = 3km/h Now, Total time = [Distance/speed]Ā Time = (54/27) +(54/3)Ā time = 2+18 =20hoursĀ
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