A train passes a station platform in 36 seconds and a man standing on the platform in 21 seconds. If the speed of the train is 54 km/hr, what is the length of the platform? Pick one
A) 877 m  B) 225 m  C) 167 m  D) 887 m  E) 265 m
Speed = (54 * 5/18) m/sec = 15 m/sec. Length of the train   = (15 x 21)m = 315 m. Let the length of the platform be x meters. Then, (x + 315)/36 = 15   ==&gt; x + 315 = 540 ==&gt; x   = 225 m.   Answer: 225 m
<result>B</result>
A train passes a station platform in 36 seconds and a man standing on the platform in 21 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?