Question

A train 180 m long crosses a milestone in 12 seconds and crosses the other train of the same length travelling in the opposite direction in 15 seconds. Find the speed of the other train.

• A. 9 m/s
• B. 11 m/s
• C. 15 m/s
• D. 10 m/s

Answer 1

Answer:

A. 9 m/s

A train 180 m long crosses a milestone in 12 seconds ⇒ Speed of the train = 180/12 = 15 m/s Let the speed of the other train be ‘S’, ⇒ Relative speed = S + 15 A train 180 m long crosses the other train of the same length travelling in the opposite direction in 15 seconds, ⇒ 15 = 360/ (S + 15) ⇒ 15S + 225 = 360 ⇒ S = 9 m/s