A train 175 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:	Options:  A) 49  B) 50  C) 12  D) 13  E) 68
Speed of the train relative to man = (175/10) m/sec = (35/2) m/sec. [(35/2) * (18/5)] km/hr = 63 km/hr. Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr. x - 5 = 63 ==&gt; x = 68 km/hr.   Answer: Option 68
<result>E</result>
A train 175 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: