A train crosses a 180-meter-long platform in 20 seconds and a man standing on the platform in 12 seconds. What is the length of the train?
Show answer & explanation
Correct answer: A
Explanation
Let the length of the train be x meters.
It crosses the man in 12 seconds,
Speed = x/12 m/s.
It crosses the platform in 20 seconds,
(x + 180)/20 = x/12
12(x + 180) = 20x
12x + 2160 = 20x
8x = 2160
x = 270 meters