Pipe A can fill a tank in 12 minutes whereas pipe A along with pipe B can fill the same tank in 8 minutes. In what time pipe B alone can fill the tank?

24 min 20 min 25 min 22 min

24 min

Following chart will be obtained with the help of LCM method: Efficiency of Pipe A = 2  Efficiency of Pipe A + B = 3 Efficiency of Pipe B = 1 Thus, Pipe B will take 24 mins to fill the tank alone.