Question 1161919
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3. What if the desired final mixture was changed to yield a 35% mixture containing pure lemon juice?
a. How many gallons of a 20% solution should be mixed with 15 gallons of a 70% solution to yield a final mixture of lemonade containing 35% of pure lemon juice? Write your answer in complete sentences.
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Two "juice" concentrations to start with:  20% and 70%.
Given,  15 gallons of the 70%;
How much of the 20% to produce mix of 35%?


Lemon content of the parts = lemon content of the whole mix


{{{20x+70*15=35(x+15)}}}
Simplify and solve.