Question 994150
Suppose that one solution contains 50% alcohol and the other solution contains 80% alcohol. How many liters of each solution should be mixed to make 10.5 of a 70% solution? 
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Equation::
alcohol + alcohol = alcohol
0.50x + 0.80(10.5-x) = 0.70*10.5
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50x + 80*10.5 - 80x = 70*10.5
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-30x = -10*10.5
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x = (1/3)10.5
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x = 3.5 liters (amt. of 50% solution needed)
10.5-x = 7 liters (amt. of 80% solution needed)
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Cheers,
Stan H.

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