A 250 m long train is running at a speed of 55 Km/hr. It crossed a platform of length 520 m in ? Choose the correct choice from the following choices:
A) 40.4 sec
B) 40.5 sec
C) 50.4 sec
D) 50.5 sec
E) 60.4
Speed = 55 Km/hr   (to convert km/hr in to M/s)   = 55 x 5/18 M/s   Distance = 250 m + 520 m ( If questions is about train crossing a post you need to consider only the length of Train, )   = 770 m   Time = Distance / Speed   = 770 x 18 / (5 x 55)   = 50.4 sec   correct 40.4 secnswer: option a
<result>A</result>
A 250 m long train is running at a speed of 55 Km/hr. It crossed a platform of length 520 m in ?