Two good train each 100 m long, are running in opposite directions on parallel tracks. Their speeds are 45 km / hr and 30 km /hr respectively. Find the time taken by the slower train to pass the driver of the faster one.	Choose the correct choice from the following answers:
A) 1.2 sec	B) 2.4 sec	C) 4.8 sec	D) 9.6 sec	E) None
Sol.   Relative Speed = (45 + 30) km / hr   = (75 x 5 / 18) m/sec   = (125/6) m/sec.   Distance covered = (100+ 100) m = 1000 m.   Required time = (200 x 6 / 125) sec = 9.6 sec.   Answer 9.6 sec
<result>D</result>
Two good train each 100 m long, are running in opposite directions on parallel tracks. Their speeds are 45 km / hr and 30 km /hr respectively. Find the time taken by the slower train to pass the driver of the faster one.