Two trains of length 150 m and 200 m are 100 m apart. They start moving towards each other on parallel tracks, at speeds 54 kmph and 72 kmph. In how much time will the trains cross each other?  Choose the correct choice from the following choices
A) 100/7 sec	B) 80/7 sec	C) 57/7 sec	D) 110/7 sec	E) 50/7 sec
Relative speed = (54 + 72)* 5/18 = 7 * 5= 
<gadget id="calculator">7 * 5</gadget>
<output>35</output>
35 mps.   The time required= d/s = (150 + 100 + 300)/35   = 550/35 = 110/7 sec.   ANSWER:110/7 sec
<result>D</result>
Two trains of length 150 m and 200 m are 100 m apart. They start moving towards each other on parallel tracks, at speeds 54 kmph and 72 kmph. In how much time will the trains cross each other?