Question 213388
Let  x  =  gallons  of  pure(100%) alcohol  added
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x(1.00) +20(.15) = (20 +x)(.25)
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x+3=5+.25x,,,,,,,,,alcohol  balance
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,75 x = 2
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x=2.67 gallons
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check,,,2.67 +3 = 22.67 * .25 = 5.67,,,,,ok
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