Two trains, 250 metres and 150 metres long respectively, are running on parallel lines. If they are running in the same directions, the faster train crosses the slower train in 40 seconds. If they are moving in the opposite direction they pass each other in eight seconds. What is the speed of the slower train? Pick one.
A) 108kmph	B) 82kmph	C) 92 kmph	D) 72 kmph	E) 87 kmph
Let the speed of faster train be f and slower train be y.   Time taken to cross each other traveling in the same direction = 250 +150/ (x-y) = 40………(1)   Time taken to cross each other traveling in the opposite direction = 250+150 /(x+y) = 8 …….(2)   From (1) and (2) f= 30 m/s and s = 20 m/s   Speed of slower train = 20 * 18/5= 
<gadget id="calculator">20 * 18/5</gadget>
<output>72</output>
72 kmph   Answer : 72 kmph
<result>D</result>
Two trains, 250 metres and 150 metres long respectively, are running on parallel lines. If they are running in the same directions, the faster train crosses the slower train in 40 seconds. If they are moving in the opposite direction they pass each other in eight seconds. What is the speed of the slower train?