three pipes A , B , and C can fill a tank in 6hours After woorking irt at togethr - PSA - Quantitative Reasoning

Question

three pipes A , B , and C can fill a tank in 6hours After
woorking irt at togethr for 2 hrs, C is closed and A and B can fill
the remaining part in 7 hrs How much time will C take alone to fill
the tank ?

Ankush Jain · Accepted Answer

Given three pipes A, B and C can fill a tank in 6 hours Now, part filled by all 3 pipes in 2 hours $= \frac{2}{6} = \frac{1}{3}$ Now, remaining unfilled part $= 1 - \frac{1}{3} = \frac{2}{3}$ Therefore, (A+B)'s 7 hour's work $= \frac{2}{3}$ Similarly, (A+B)'s 1 hour's work $= \frac{2}{21}$

C's 1 hour's work = { (A + B + C)'s 1 hour's work } - { (A + B)'s 1 hour's work } $= \frac{1}{6} - \frac{2}{21} = \frac{7 - 4}{42} = \frac{3}{42} = \frac{1}{14}$

C alone can fill the tank in 14 hours

three pipes A , B , and C can fill a tank in 6hours. After woorking irt at togethr for 2 hrs, C is closed and A and B can fill the remaining part in 7 hrs . How much time will C take alone to fill the tank ?