SOLUTION: ok....Suppose that a 12 quart radiator contains a 20% solution of antifreeze. how much solution needs to be drained out and replaced with pure antifreeze to obtain a 40% solution o

Question 676013: ok....Suppose that a 12 quart radiator contains a 20% solution of antifreeze. how much solution needs to be drained out and replaced with pure antifreeze to obtain a 40% solution of antifreeze....
Answer by nerdybill(7384) (Show Source): You can put this solution on YOUR website!
Suppose that a 12 quart radiator contains a 20% solution of antifreeze. how much solution needs to be drained out and replaced with pure antifreeze to obtain a 40% solution of antifreeze
.
Let x = amount (quarts) drained and replaced
then
.20(12-x) + x = .40(12)
2.4-.20x + x = 4.8
2.4 + .80x = 4.8
.80x = 2.4
x = 2.4/.80
x = 3 quarts

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