Two trains of length 250 m and 120 m are 50 m apart. They start moving towards each other on parallel tracks, at speeds 64 kmph and 42 kmph. After how much time will the trains meet?  Choose the correct option.
A) 15/10
B) 17/10
C) 16/10
D) 18/10
E) 16/10
They are moving in opposite directions, relative speed is equal to the sum of their speeds.   Relative speed = (64 + 42)*5/18 = 7*5 = 29.4 mps.   The time required = d/s = 50/29.4 = 17/10 sec.   Answer:17/10
<result>B</result>
Two trains of length 250 m and 120 m are 50 m apart. They start moving towards each other on parallel tracks, at speeds 64 kmph and 42 kmph. After how much time will the trains meet?