Problema Solution

The cooling system of a car has a capacity of 25 liters. If the system is currently filled with the mixture that is 60% antifreeze, how much of this mixture should be drained and replaced with pure antifreeze so that the system is filled with a solution that is 90% antifreeze?

Answer provided by our tutors

We can write:


.6x+1(25-x)=.9(25)


where 'x', '25-x', and '25' represent the liters of '.6', '1', and '.9' antifreeze solutions respectively.


Using Algebrator to solve for 'x', we get:

x=6.25liters


This is the amount of the 60% solution needed. Therefore '25-6.25', 18.75 liters, would have to be drained.