Question

Two pipes fill a cistern in 15 and 10 min it takes 2 minutes extra due to leakage in cistern.find out the time which the leak will take

Answer 1

Part filled in 4 minutes =4(1/15+1/20) = 7/15

 

Remaining part =(1-7/15) = 8/15

 

Part filled by B in 1 minute =1/20 : 8/15 :: 1:x 

x = (8/15*1*20) = 1023min = 10min 40sec1023min = 10min 40sec

The tank will be full in (4 min. + 10 min. + 40 sec.) = 14 min. 40 sec