A train moves past a post and a platform 264 m long in 8 seconds and 20 seconds respectively. What is the speed of the train?
Pick:
A) 79.0 B) 79.2 C) 79.5 D) 79.7 E) 79.6
Let x is the length of the train and v is the speed   Time taken to move the post = 8 s   =&gt; x/v = 8   =&gt; x = 8v --- (1)   Time taken to cross the platform 264 m long = 20 s   (x+264)/v = 20   =&gt; x + 264 = 20v ---(2)   Substituting equation 1 in equation 2, we get   8v +264 = 20v   =&gt; v = 264/12= 
<gadget id="calculator">264/12</gadget>
<output>22</output>
22 m/s= 22×36/10 km/hr = 79.2 km/hr   Answer is 79.2.
<result>B</result>
A train moves past a post and a platform 264 m long in 8 seconds and 20 seconds respectively. What is the speed of the train?