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 sec. The speed of the train is?  Choose one.
A) 40	B) 50	C) 60	D) 70	E) 80
Speed of the train relative to man = 125/10 = 25/2 m/sec.   = 25/2 * 18/5= 
<gadget id="calculator">25/2 * 18/5</gadget>
<output>45</output>
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: Option 50
<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 sec. The speed of the train is?