A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 28 minutes. When both pipes are opened, find when the cistern will be full?
A. 60 min
B. 80 min
C. 70 min
D. 48 min
Answer:C
A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 28 minutes. When both pipes are opened, find when the cistern will be full?
A. 60 min B. 80 min C. 70 min D. 48 min