Question
A boat running downstream covers a distance of 28 km in
2 hrs while it covers the same distance upstream in 7 hrs. Then speed of the boat in still water isSolution
Let the speed of boat in still water be a km/hr and that of stream be b km/hr. Therefore, 28/(a + b)= 2 ⇒ a + b = 14 ………..(i) 28/(a – b)= 7 ⇒ a + b = 4 ………..(ii) On adding, eq (i) and (ii) ⇒ 2a = 18 km/hr ⇒ a = 9 km/hr
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