http://goo.gl/9JPA0m<br /><br />Learn cool ways to do easy calculations<br /><br />Pipes and Cistern:<br />Questions based on this topic have outlet and inlet. Outlet: A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet.<br /> <br />If a pipe can fill a tank in x hours, then :<br />part filled in 1 hour = 1 / x.
