A train passes a station platform in 36 sec and a man standing on the platform in 20 sec. If the speed of the train is 90 km/hr. What is the length of the platform?
Choose the most appropriate option
A) 229  B) 240  C) 400  D) 277  E) 221
Speed = 90 * 5/18= 
<gadget id="calculator">90 * 5/18</gadget>
<output>25</output>
25 m/sec.   Length of the train= 25 * 20= 
<gadget id="calculator">25 * 20</gadget>
<output>500</output>
500 m.   Let the length of the platform be x m . Then,   (x + 500)/36= 25 =&gt; x = 400 m.   Answer: 400
<result>C</result>
A train passes a station platform in 36 sec and a man standing on the platform in 20 sec. If the speed of the train is 90 km/hr. What is the length of the platform?