Two trains are moving at 65 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?\nOptions:\n(A) 6 2/3 sec\n(B) 7 1/7 sec\n(C) 7 2/2 sec\n(D) 8 1/2 sec\n(E) 7 1/9 sec
Stream of thoughts:
(A)
70 + 65 = 135 * 5/18 = 75/2 mps\nD = 150 + 100 = 250 m\nT = 250 * 2/75 = 20/3 - 6 2/3 sec.

The final answer: (A)