Train A crosses a man standing on a platform in 10.8 seconds. Train B crosses train A is running in the opposite direction in 16 seconds. If the length of train A and B is 180 m and 220 m respectively, then what is the time taken by train B to cross a car is running in the same direction at the speed of 20 kmph?
A. 78.2 seconds
B. 76.2 seconds
C. 79.2 seconds
D. 80.2 seconds
E. None of these
Sol:
Speed of train A = 180/(10.8 * 5/18)
= 60 kmph
Speed of train B = x
180 + 220 = (60 + x) * 5/18 * 16
x = 90 – 60 = 30 kmph
Required time = 220/((30 – 20) * 5/18)
= 79.2 seconds
