Two trains are moving at 60 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? Pick one
A) 5 sec B) 6 sec C) 7 sec D) 8 sec E) 9 sec

Rationale: "70 + 60 = 130 * 5 / 18 = 325 / 9 mps d = 150 + 100 = 250 m t = 250 * 9 / 325 = 7 sec answer : c"
Answer: C