SOLUTION: How much of a 70% alcohol solution and how much of a 30% alcohol solution should be mixed to make 5 liters of a 50% alcohol solution?

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Question 702760: How much of a 70% alcohol solution and how much of a 30% alcohol solution should be mixed to make 5 liters of a 50% alcohol solution?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
How much of a 70% alcohol solution and how much of a 30% alcohol solution should be mixed to make 5 liters of a 50% alcohol solution?
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50% is the average, so it's equal amounts.
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The general solution:
s = amount of 70%
t = 30%
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s + t = 5 (total solution)
70s + 30t = 5*50 (total alcohol)
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s = 5-t
7s + 3t = 25
7(5-t) + 3t = 25
--> t = 2.5
s = 2.5
same answer