<PRE><B>Question 455819</B>
He mixes a solution that is 10% acid with a solution that is 30% acid. How much of the 30% acid solution will be needed to make 40 liters of solution that is 25% acid?
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Equation:
acid + acid = acid
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0.10x + 0.30(40-x) = 0.25*40
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Multiply thru by 100 to get:
10x + 30*40 - 30x = 25*40
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-20x = -5*40
x = 10 liters (amt. of 10% solution needed)
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40-x = 30 liters (amt. of 30^ acid needed)
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Cheers,
Stan H.
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