Quantitative Aptitude Ques 118

Question: Pipe A can fill an empty tank in 6 h and pipe B in 8 h. If both the pipes are opened and after 2 h pipe A is closed, then how much time pipe B will take to fill the remaining tank?

Options:

A) $ 7\frac{1}{2}h $

B) $ 3\frac{1}{3}h $

C) $ 2\frac{2}{5}h $

D) $ 2\frac{1}{3}h $

Show Answer

Answer:

Correct Answer: B

Solution:

  • A’s one hour’s work $ =\frac{1}{6} $ B’s one hour’s work $ =\frac{1}{8} $ $ (A+B)’s $ two hour’s work $ =2( \frac{1}{8}+\frac{1}{6} )=\frac{28}{48} $

$ \therefore $ Remaining work $ =1-\frac{28}{48}=\frac{20}{48} $ Time taken by pipe B to complete remaining work $ =\frac{\frac{20}{48}}{\frac{1}{8}}=\frac{20}{48}\times 8=\frac{20}{6}=3\frac{1}{3}h $