Question
1200 metres long train crosses a man who is moving in
the same direction with a certain speed, in 30 seconds. If the same train can cross a tree in 20 seconds with the same speed, then find the speed of the man.Solution
Speed of train = 1200/20 = 60 m/sec Let the speed of the man be βsβ m/sec Relative speed of the train = (60 β s) m/sec According to the question, (60 β s) = 1200/30 Or, s = 60 β 40 = 20 Therefore, speed of the man = 20 m/sec
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