Two trains of length 210 m and 120 m are 160 m apart. They start moving towards each other on parallel tracks, at speeds 74 kmph and 92 kmph. After how much time will the trains meet?
Choose the correct choice:
A) 35 / 10 B) 31 / 10 C) 31 / 10 D) 36 / 10 E) 37 / 10

Rationale: they are moving in opposite directions , relative speed is equal to the sum of their speeds . relative speed = ( 74 + 92 ) * 5 / 18 = 46.1 mps . the time required = d / s = 160 / 46.1 = 35 / 10 sec . answer : a
Answer: A