Two trains of length 200 m and 300 m are 200 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) 70/8	B) 70/7	C) 70/5	D) 70/3	E) 70/1
Relative speed = (36 + 72)* 5/18 = 6 * 5= 
<gadget id="calculator">6 * 5</gadget>
<output>30</output>
30 mps.   The time required= d/s = (200 +200 + 300)/30   = 700/30= 70/3 sec.   Answer: 70/3
<result>D</result>
Two trains of length 200 m and 300 m are 200 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?