Question

Two pipes P₁ and P₂ can fill a tank in 6 h and 3 h, respectively. Both the pipes are opened simultaneously and pipe P₁ is closed after 1 h. Find the time taken by P₂ to fill the remaining part of the tank (in hours).

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Answer 1

Given:

• Two pipes P₁ and P₂ can fill a tank in 6 h and 3 h, respectively.

• Both the pipes are opened simultaneously and pipe P₁ is closed after 1 h.

To Find:

• The time taken by P₂ to fill the remaining part of the tank (in hours).

Solution:

P₁ and P₂ together fill the tank in 1hr is

$\sf{ \frac{1}{6} + \frac{1}{3}}$

Therefore, remaining part of the tank to be filled is

$\sf{1 - \bigg( \frac{1}{6} + \frac{1}{3}\bigg) = \frac{3}{6} = \frac{1}{2} }$

So, time taken by P₂ to fill remaining part(1/2) of the tank is

$\sf{\frac{1}{2}\div\frac{1}{3}= \frac{1}{2}\times \frac{3}{1} = 1 \frac{1}{2}}h$