Two pipes A and B can fill a tank in 12 and 24 minutes respectively. If both the pipes are used together, how long will it take to fill the tank?
Choose the correct choice from the following options.
A) 9 min	B) 8 min	C) 4 min	D) 6 min	E) None of these
Explanation:   Tank can be filled by pipe A in 12 minutes and pipe B in 24minutes.   =&gt; Part filled by A in 1 minute= 1/12   =&gt; Part filled by 8 min in 1 minute= 1/24   =&gt; Part filled by both in 1 minute= 1/12 + 1/24   = 3/24=1/8   Time taken to fill the entire tank = 8 minutes   ANSWER 8 min
<result>B</result>
Two pipes A and B can fill a tank in 12 and 24 minutes respectively. If both the pipes are used together, how long will it take to fill the tank?