Question 622571
A 45 gallon barrel contains a mixture with a concentration of 30%. How much of this mixture must be withdrawn and replaced by 100% concentrate to bring the mixture up to 50% concentration?
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let x=mixture to be withdrawn and replaced
45-x=remaining 30% mixture
30%(45-x)+100%x=50%*45
13.5-.3x+x=22.5
.7x=9
x≈12.86
gallons of mixture to be withdrawn and replaced≈12.86