Two pipes A and B can fill a tank in 12 and 24 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?
Choose the correct choice from the following options.
A) 8 min	B) 28 min	C) 18 min	D) 5 min	E) 6min
Explanation :   Part filled by pipe 8 min in 1 minute= 1/12   Part filled by pipe B in 1 minute= 1/24   Part filled by pipe 8 min and pipe B in 1 minute= 1/12+1/24=1/8   i.e., both the pipe together can fill the tank in 8 minutes   8 minnswer is 8 min
<result>A</result>
Two pipes A and B can fill a tank in 12 and 24 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?