You can put this solution on YOUR website! How many liters containing 8% acid solution should be added to 20 liters containing 60% acid in order to obtain a 40% acid solution?
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= 0.4.
The numerator is the volume of the pure acid in the mixture, obtained by adding the volumes of the pure acid in components;
the denominator is the total liquid volume.
x is the unknown volume under the question.
Simplify and solve for x.