A train, 150 m long, passes a pole in 15 seconds and another train of the same length travelling in the opposite direction in 12 seconds. The speed of the second train is :

A. 45 km/hr

B. 48 km/hr

C. 52 km/hr

D. 54 km/hr

Answer: Option D

Solution(By Examveda Team)

Speed of the first train :
= $$\frac{150}{15}$$ = 10 m/s
Time taken by trains to cross each other = 12 sec
And, relative speed of two trains :
= $$\frac{150 + 150}{12}$$
= 25 m/s
∴ Speed of the second train :
= (25 - 10) × $$\frac{18}{5}$$
= 54 km/hr