Question 473567
how many liters of pure alcohol must be mixed with 20 liters of 25% alcohol solution to get 85% mixture?

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Eqution:
alcohol + alcohol = alcohol
x + 0.25*20 = 0.85(x+20)
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Multiply thru 100 to get:
100x + 25*20 = 85x + 85*20
15x = 60*20
x = 5 liters (amt. of pure alcohol needed)
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Cheers,
Stan H.
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