Question 1115622
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1) How much pure acid must be added to 10 ounces of 40% pure acid to give a mixture of 50% pure acid? 
2) How much pure alcohol must be mixed with a mixture containing 20% alcohol to have 2 gallons of a mixture with 50% alcohol? 
Can you show me the steps with the anwser with them, please!
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(1)
x, ounces of the pure, 100% acid to add

{{{x+0.4*10=0.5(x+10)}}}
Solve this for x.



(2)
x, number of gallons of 100% pure alcohol to add
2-x, amount of gallons of the 20% alcohol to add

{{{x+0.2(2-x)=0.5*2}}}
Solve for x and evaluate 2-x.


You need to do the algebra and the necessary arithmetic.