Two taps A and B can fill a tank in 5 hours and 20hours respectively. If both the taps are open then due to a leakage, it took 30 minutes more to fill the tank. If the tank is full, how long will it take for the leakage alone to empty the tank?
Select:
A) 24 hr  B) 36 hr  C) 18 hr  D) 42 hr  E) 30 hr
Part filled by A+B in 1 hour = 1/5 + 1/20 = 1/4   A and B together can fill the tank in 4 hour   Work done by the leak in 1 hour = 1/4 - 2/9 = 1/36   leak will empty the tank in 36 hours.   Answer is 36 hr
<result>B</result>
Two taps A and B can fill a tank in 5 hours and 20hours respectively. If both the taps are open then due to a leakage, it took 30 minutes more to fill the tank. If the tank is full, how long will it take for the leakage alone to empty the tank?