Question
A boat running downstream covers a distance of 42 km in
6 hrs and covering the same distance upstream in 14 hrs. What is the speed of a boat in still water?Solution
Downstream speed = 42/6 = 7 km/hr Upstream speed = 42/14 = 3 km/hr So speed of boat in still water = (7 + 3)/2 = 5 km/hr
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(ii) Steam engin...
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