Question 517994
Pure acid is to be added to a 10% acid solution to obtain 90L of 60% solution. What amounts of each should be used? 
How many liters of 100% pure acid should be used to make the solution?
Equation:
1.00x + 0.10(90-x) = 0.6*90
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100x + 10*90 - 10x = 60*90
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90x = 50*90
x = 50 L (amt. of pure acid needed)
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How many liters of the 10% solution should be used in the mixture?
90-x = 90-50 = 40L (amt of 10% solution needed.
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Cheers,
Stan H.
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