A train 1000 m long passed a pole in 20 sec. How long will it take to pass a platform 500 m long?  Choose the correct option.
A) 22
B) 24
C) 26
D) 28
E) 30
Speed = 1000/20= 
<gadget id="calculator">1000/20</gadget>
<output>50</output>
50 m/sec.   Required time= (1000 + 500)/50= 
<gadget id="calculator">(1000 + 500)/50</gadget>
<output>30</output>
30 sec.   Answer:30
<result>E</result>
A train 1000 m long passed a pole in 20 sec. How long will it take to pass a platform 500 m long?