A cistern is normally filled in 10 hours but takes two hours longer to fill because of a leak in its bottom. If the cistern is full, the leak will empty it in? Choose the correct choice.
A) 33
B) 88
C) 60
D) 99
E) 11
1/10 - 1/x = 1/12   x = 60   Answer: 60
<result>C</result>
A cistern is normally filled in 10 hours but takes two hours longer to fill because of a leak in its bottom. If the cistern is full, the leak will empty it in?