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 the correct option: A) 16 km/hr B) 50 km/hr C) 19 km/hr D) 15 km/hr E) 87 km/hr
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 - 5) km/hr. x - 5 = 45 ==&gt; x   = 50 km/hr.   Answer: 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: