Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?

Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?

A 12 min

B 15 min

C 25min

D 50 min

Solution

Correct Answer: Option A

shortcut=xy/x+y

=(20×30)/50

=12