Two trains of length 150 m and 250 m are 150 m apart. They start moving towards each other on parallel tracks, at speeds 36 kmph and 72 kmph. In how much time will the trains cross each other?
Choices:
A) 55/3 B) 55/7 C) 55/6 D) 55/8 E) 55/9
Relative speed = (36 + 72)* 5/18 = 6 * 5= 
<gadget id="calculator">6 * 5</gadget>
<output>30</output>
30 mps.   The time required= d/s = (150 + 150 + 250)/30   = 550/30 = 55/3 sec.   55/3nswer: 55/3
<result>A</result>
Two trains of length 150 m and 250 m are 150 m apart. They start moving towards each other on parallel tracks, at speeds 36 kmph and 72 kmph. In how much time will the trains cross each other?