a train length 100 m going with speed 10m/sec another train 150m long going with speed 15m/sec.the distance between two train is 50m.then how much time second train will take to cross the first train?
Select:
A) 60sec
B) 40sec
C) 30sec
D) 45sec
E) 1min10sec
net speed=15-10= 
<gadget id="calculator">15-10</gadget>
<output>5</output>
5m/sec   net distance=100+150+50= 
<gadget id="calculator">100+150+50</gadget>
<output>300</output>
300   total time=300/5= 
<gadget id="calculator">300/5</gadget>
<output>60</output>
60sec   answer 60sec
<result>A</result>
a train length 100 m going with speed 10m/sec another train 150m long going with speed 15m/sec.the distance between two train is 50m.then how much time second train will take to cross the first train?