Question

A scientist needs 60 liters of a 40% solution of alcohol. He has a 30% solution and a 60% solution available. How many liters of the 30% solution and how many liters of the 60% solution should he mix to make the 40% solution?

Answer 1

A scientist needs 60 liters of a 60% acid solution. He currently has a 40% solution and a 70% solution. How many liters of each does he need to make the needed 60 liters of 60% acid solution?

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Equation:

acid + acid = acid

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0.40x + 0.70(60-x) = 0.60*60

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40x + 70*60 - 70x = 60*60

 

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-30x = -10*60

x = 20 liters

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Gabe needs 20 liters of the 40% solution.

He also needs 40 liters of the 70% solution.