arithmetic - a train passes a platform in 36 seconds the same train passes a man standing on the platform in 20 seconds if the speed of the train is 54 kmhr the length of the platform is - skillgun

Speed of the train = 54 km/hr = (54×10)/36 m/s = 15 m/s
Length of the train = speed × time taken to cross the man = 15×20 = 300 m
Let the length of the platform = L
Time taken to cross the platform = (300+L)/15
=> (300+L)/15 = 36
=> 300+L = 15×36 = 540
=> L = 540-300 = 240 meter