A train crosses a 250 m long platform in 15 seconds, while it crosses a pole in 2.5 seconds, what is the length of the train?

50 m

Let length of train = x m

Length of platform =250 m

Distance traveled by train while crossing platform = (x + 250) m

Distance traveled by train while crossing pole = x m

ATQ,

(x + 250)m distance covered in = 15 sec

x m distance covered in = 2.5 sec

It means train takes ⇒

15 -2.5 = 12.5 sec to cover a distance of ⇒ (x+250) - x = 250m

⇒ Speed of train = \(\frac{250}{12.5}\) = 20 m/sec

So,

Distance traveled by train while crossing pole = Length of train = speed x time = 20 × 2.5 = 50 m