Aptitude::Pipes & Cistern

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Important Formulas

 

Inlet: A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet.

Outlet: A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet.

* If a pipe can fill a tank in x hours, then:  part filled in 1 hour = 1/x

* If a pipe can empty a tank in y hours, then:  part emptied in 1 hour = 1/y.

* If a pipe can fill a Tank/Cistern in x hours and another pipe can empty the full Tank/Cistern in y hours (where y > x),

            Then on opening both the pipes, then the net part filled in 1 hour = (1/x -1/y).

* If a pipe can fill a Tank/Cistern in x hours and another pipe can empty the full Tank/Cistern in y hours (where x > y),

            Then on opening both the pipes, then the net part emptied in 1 hour = (1/y - 1/x).