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 81 km/hr. What is the length of the platform?  Choose the most appropriate option: A) 240 B) 288 C) 277 D) 360 E) 422
Speed = 81 * 5/18= 
<gadget id="calculator">81 * 5/18</gadget>
<output>45/2 = around 22.5</output>
22.5 m/sec.   Length of the train= 22.5 * 20= 
<gadget id="calculator">22.5 * 20</gadget>
<output>450</output>
450 m.   Let the length of the platform be x m . Then,   (x + 450)/36= 22.5 =&gt; x = 360 m.   Answer: 360
<result>D</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 81 km/hr. What is the length of the platform?