Oh yes, you all will be my algebra tutors.
My word problem is this:
A radiator holds 20L of 20% antifreeze solution. For this particular model of car it should be 40%. How much do you need to drain and refill with 100% solution to make it 40%?
I know that the amount that needs to be refilled is my variable, x. What I can't figure out is how to set up the equation. Anyone want to help me understand this?
Actual answer under tags.
The answer is 5L per the back of the book