Question

A cistern is normally filled in 8 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 ?
A) 20 hrs
B) 28 hrs
C) 36 hrs
D) 40 hrs

Answer 1

Q:

A cistern is normally filled in 8 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    ?

A) 20 hrs
B) 28 hrs
C) 36 hrs
D) 40 hrs

Answer:   A) 20 hrs 

Explanation:

1/8 - 1/x = 1/10
 => x = 40 hrs