Q: Two trains are moving at 50 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) 7 1/2 sec\n(B) 7 1/7 sec\n(C) 7 8/2 sec\n(D) 7 1/9 sec\n(E) 7 2/2 sec Let's give some random thoughts before answering.
User
70 + 50 = 120 * 5/18 = 100/3 mps\nD = 150 + 100 = 250 m\nT = 250 * 3/100 = 15/2 = 7 1/2 sec
Therefore, the answer is (D).
Assistant