SOLUTION: A 55-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 How much of this mixture must be withdrawn and replaced by 100% concentrate to bring the mixture up to 50% concen
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Question 192099: A 55-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 How much of this mixture must be withdrawn and replaced by 100% concentrate to bring the mixture up to 50% concentrate? Answer by RAY100(1637) (Show Source):
You can put this solution on YOUR website! total is 55 gal
at 30%, solute is 30% 0f 55 or .3*55= 16.5 gal
required to have 50% of 55 = .50*55= 27.5 gal
16.5 - .3x +1.00x = 27.5
subt 16.5 both sides and simplify
(1-.3)x= 11
.7x = 11
divide by .7
x=15.714 or in sig fig (16) ANSWER
checking
.3*15.714 = 4.714
16.5 - 4.714+15.714 = 27.5 ok
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