A 12 qrt. cooling system is checked and found to be filled with a solution that is 40 % antifreeze. The desired strength of the solution is 60% antifreeze. how many quarts of solution need to be drained and replaced with pure antifreeze to reach the desired strength.

Answer 1

If q quarts are to be drained, then

.40(12-q) + 1.00q = .60(12)
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