A train moving at a speed of 40 km / h passes the platform in 4 minutes 12 seconds.

A train moving at a speed of 40 km / h passes the platform in 4 minutes 12 seconds. Determine the length of the platform (in meters) if the train is 1600 m long.

1. Determine what distance the train travels while moving past the platform. If the train’s own speed is 40 km / h, and it spends 4 minutes 12 seconds driving past the platform:

40 km / h = 40 * 1000/3600 = 40,000/3600 = 100/9 m / s;

4 minutes 12 seconds = 4 * 60 + 12 = 240 + 12 = 252 seconds;

100/9 * 252 = 25200/9 = 2800 m, a train is passing;

2. Find out the length of the platform, if the total length of the train and platform is 2800 m, and the length of the train is 1600 m:

2800 – 1600 = 1200 m, platform length;

Answer: platform length 1200 m.