Question
700 metres long train crosses a man who is moving in the
same direction with a certain speed, in 25 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 = 700/20 = 35 m/sec Let the speed of the man be ‘s’ m/sec Relative speed of the train = (35 – s) m/sec According to the question, (35 – s) = 700/25 Or, s = 35 – 28 = 7 Therefore, speed of the man = 7 m/sec
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