70 + 90 = 150 * 5/18 = 400/9 mps
D = 150 + 100 = 250 m
T = 250 * 9/400 = 45/8 sec
Two trains are moving at 90 kmph and 70 kmph in opposite directions. Their lengths are 150 m and 100 m respectively. The time they will take to pass each other completely is?
[A] 42/5 sec
[B] 45/8 sec
[C] 40/6 sec
[D] 37/6 sec
[E] 42/4 sec