Question 189461
    How many quarts of antifreeze must be added to 8 quarts of a 50% antifreeze solution to obtain a 60% antifreeze solution?
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Let x = quarts of antifreeze added
then
"amt of antifreeze originally" + "added antifreeze" = "desired mix of antifreeze"
.50(8) + x = .60(8+x)
4 + x = 4.8 + .60x
4 + .40x = 4.8
.40x = .8
x = .8/.40
x = 2 quarts