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 ?	Choose the correct answer.
A) 45 kmph  B) 25 kmph  C) 30 kmph  D) 50 kmph  E) None of these
Explanation:   Speed of the train relative to man = (125/10) m/sec = (25/2) m/sec.   [(25/2) x (18/5)] km/hr = 45 km/hr.   Let the speed of the train be 'S' km/hr.   Then, relative speed = (S - 5) km/hr.   S - 5 = 45 =&gt; S = 50 km/hr.   ANSWER IS 50 kmph
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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 ?