Two trains are running at 40 kmph and 20 kmph respectively in the same direction.Fast train completely passes a man sitting in the slower train in 7 seconds.What is the length of the fast train? Select the correct option
A) 23 m
B) 38 8/9 m
C) 27m
D) 27 7/9m
E) 33 7/9m
relative speed=20kmph=50/9m/sec   length of the train=50/9*7= 38 8/9   ANSWER:38 8/9 m
<result>B</result>
Two trains are running at 40 kmph and 20 kmph respectively in the same direction.Fast train completely passes a man sitting in the slower train in 7 seconds.What is the length of the fast train?