A fill pipe can fill 1/2 of cistern in 20 minutes. In how many minutes, it can fill 1/2 of the cistern?	Select:
A) 5min	B) 10min	C) 15min	D) 20min	E) 25min
Required time = 20*2*1/2= 
<gadget id="calculator">20*2*1/2</gadget>
<output>20</output>
20 minutes   Answer is 20min
<result>D</result>
A fill pipe can fill 1/2 of cistern in 20 minutes. In how many minutes, it can fill 1/2 of the cistern?