Question
A train 150 meters long crosses a man running in the
same direction at a speed of 9 km/h in 15 seconds. It then crosses a platform in 25 seconds. Find the length of the platform and the speed of the train.Solution
Speed of train relative to man = 150/15 = 10 m/s = 36 km/h. Speed of train = 36 + 9 = 45 km/h. Speed = 45 × 5/18 = 25/2 m/s. Length of platform = (25 × 25/2) - 150 = 162.5 m. Correct option: c
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