A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is:
Select:  A) 45 km/hr  B) 50 km/hr  C) 54 km/hr  D) 55 km/hr  E) 58 km/hr
Speed of the train relative to man = 125/10	m/sec   = 25/2	m/sec.   2   = 25/2	x	18/5	km/hr   = 45 km/hr.   Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr.   x - 5 = 45 x = 50 km/hr.   Option 50 km/hr
<result>B</result>
A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is: