<PRE><B>Question 758194</B>
A nurse has a solution that is 25% alcohol and another that is 50% alcohol. How much of each must he use to make 45 liters of a solution that is 40% alcohol?
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Equation:
alch + alch = alch
0.25x + 0.50(45-x) = 0.40*45
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25x + 50*45 - 50x = 40*45
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-25x = -10*45
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x = 18 liters (amt. of 25% solution needed)
45-x = 27 liters (amt. of 50% solution needed)
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