A fill pipe can fill 1/2 of cistern in 30 minutes. In how many minutes, it can fill 1/2 of the cistern?
Options:
A) 15 min
B) 20 min
C) 25 min
D) 30 min
E) 35 min
Required time = 30*2*1/2= 
<gadget id="calculator">30*2*1/2</gadget>
<output>30</output>
30 minutes   Answer is 30 min
<result>D</result>
A fill pipe can fill 1/2 of cistern in 30 minutes. In how many minutes, it can fill 1/2 of the cistern?