How much time a train 200 metres long running at the speed of 72 km/hr take to cross a bridge 180 metres in length?
Distance (Length of the train + length of the bridge) = 200 + 180 = 380 Speed of Train = 72 km/hr = 72×5/18 = 20 m/sec. Time = Distance/Speed = 380/20 = 19 sec.