A train travelling at 36 kmph takes 48 seconds to cross a bridge. It then crosses a man cycling at the rate of 9 kmph in the same direction in 20 seconds. Find the length of the bridge.

330 m

Speed = \(\frac{ Distance}{ Time}\)

Let the length of the train be x and the length of bridge be y

So, according to the question:

(36 - 9) x \(\frac{5 }{18 }\) = \(\frac{ x}{ 20}\)

27 x \(\frac{5 }{18 }\) = \(\frac{ x}{ 20}\)

x = 150

Length of the train is 150 m

According to the question,

36 x \(\frac{5 }{18 }\) =  \(\frac{ \text{150 + y}}{ 48}\)

10 = \(\frac{ \text{150 + y}}{ 48}\)

480 = 150 + y

y = 330

Thus, the length of the bridge is 330 m