A train 280 m long passed a pole in 20 sec. How long will it take to pass a platform 720 m long? Select the correct option:	A) 12 sec	B) 59 sec	C) 71 sec	D) 61 sec	E) 66 sec
Speed = 280/20= 
<gadget id="calculator">280/20</gadget>
<output>14</output>
14 m/sec.   Required time= (280 + 720)/14   = 71.4 sec.   Answer: 71 sec
<result>C</result>
A train 280 m long passed a pole in 20 sec. How long will it take to pass a platform 720 m long?