A large tank is being filled from a tap delivering water at a rate of 125L/hr. If the delivery rate were increased by 25L/hr the tank would be filled 1 hour and 20 minutes sooner.

Question

A large tank is being filled from a tap delivering water at a rate of 125L/hr. If the delivery rate were increased by 25L/hr the tank would be filled 1 hour and 20 minutes sooner.
Determine the volume of the tank.

Reiny · Answer

Let the volume be V at a rate of 125 L/h, time would be V/125 hrs at a rate of 150 L/h, time would be V/150 hrs V/125 - V/150 = 1 1/3 = 4/3 times 750 6V - 5V = 1000 V = 1000

Kyan · Answer

But why did you times by 750?

JRB · Answer

Because when you do v/125 - v/150 = 4/3, both the bottom numbers of the fraction have to be the same and there common denominator happens to be 750.

Jacob · Answer

How the haeck did you get 1 1/3