# Can you calculate the number of hours taken by C alone to fill the cistern ?

90 views

Three pipes A , B and C can fill a tank in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill it in 7 hours.
Can you calculate the number of hours taken by C alone to fill the cistern ?

posted Dec 3, 2014

+1 vote

Ans: 14 hrs
Let cistern is of 6 litres (u can assume any no.)
in first 2 hrs 2 litres were filled.then A&B takes 7 hrs to fill 4 litres.So combined speed of A&B is 4/7 lit/hr.
Let speed of C be c lit/hr. so,
4/7×2 + c×2 = 2
c=3/7 lit/hr
So time taken by C to fill whole cistern:
6÷3/7=14 hrs.
Ans=14 hrs

Similar Puzzles

Pipe A can fill a cistern in 4 hours while pipe B can empty it in 6 hours. If both of them are opened together at the same time when the tank is empty, then how many hours would be taken by them to fill it?

A cistern has three pipes A, B and C. The pipes A and B can fill it in 4 and 5 hours respectively and C can empty it in 2 hours. If the pipes are opened in order at 1, 2 and 3 am respectively..
When will the cistern be empty?

A tap can fill a cistern in 11 hours, but due to a leakage it took 13 hours to fill the cistern.
If the cistern is full, in what time will the cistern become empty due to leakage?