Question
1500 metres long train crosses a man who is moving in
the same direction with a certain speed, in 50 seconds. If the same train can cross a tree in 15 seconds with the same speed, then find the speed of the man.Solution
Speed of train = 1500/15 = 100 m/sec Let the speed of the man be ‘s’ m/sec Relative speed of the train = (100 – s) m/sec According to the question, (100 – s) = 1500/50 Or, s = 100 – 30 = 70 Therefore, speed of the man = 70 m/sec
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