<PRE><B>Question 709507</B>
A chemist has 20% and 50% solutions of acid available. How many liters of each solution should be mixed to obtain 10 liters of a 40% acid solution?
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Equation:
acid + acid = acid
0.20x + 0.50(10-x) = 0.40*10
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20x + 50*10 - 50x = 40*10
-30x = -10*10
x = 3 1/3 liters (amt. of 20% solution needed)
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10-x = 6 2/3 liters (amt. of 50% solution needed)
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Cheers,
Stan H.
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