/**//**/Two inlet pipes A and E can fill an empty cistern in 12 minutes and 36 minutes respectively. Both the pipes A and E are opened together and after some time pipe, A is closed. Thus it takes 20 minutes to completely fill the tank, then for how many minutes pipe A was open?

/**//**/Two inlet pipes A and E can fill an empty cistern in 12 minute

1.	////Two inlet pipes A and E can fill an empty cistern in 12 minutes and 36 minutes respectively. Both the pipes A and E are opened together and after some time pipe, A is closed. Thus it takes 20 minutes to completely fill the tank, then for how many minutes pipe A was open?
A.	5\(\frac{1}{3}\) minutes
B.	6 minutes
C.	7 minutes
D.	3 minutes
Answer» B. 6 minutes