Train M is 280 meters long and crosses a pole in 10 seconds. Train N is 320 meters long and crosses a 320-meter-long platform in 20 seconds. Find the time taken by both trains to cross each other while they are moving in opposite directions.

ATQ, Train M crosses a pole, so the distance covered is equal to the length of Train M. Speed of Train M = 280/10 = 28 m/s. Train N crosses a 320-meter-long platform. Total distance covered by Train N = 320 + 320 = 640 meters. Time taken by Train N = 20 seconds. Speed of Train N = 640/20 = 32 m/s. When two trains run in opposite directions, relative speed = sum of their speeds. Relative speed = 28 + 32 = 60 m/s. Total distance to be covered = length of Train M + length of Train N Total distance = 280 + 320 = 600 meters. Time taken = 600/60 Time taken = 10 seconds