A train 125 m long passes a man, running at 7 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is?  Choose the correct choice from the following choices:  A) 11  B) 50  C) 52  D) 65  E) 22
Speed of the train relative to man = (125/10) m/sec = (25/2) m/sec. [(25/2) * (18/5)] km/hr   = 45 km/hr. Let the speed of the train be x km/hr. Then, relative speed = (x - 7) km/hr. x - 7 = 45 ==&gt; x   = 52 km/hr.   Answer:52
<result>C</result>
A train 125 m long passes a man, running at 7 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is?