SOLUTION: A cough medicine contains 25% alcohol. How much liquid should a pharmacist add to 120 milliliters of the cough medicine so that it contains only 20% alcohol?

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Question 129247: A cough medicine contains 25% alcohol. How much liquid should a pharmacist add to 120 milliliters of the cough medicine so that it contains only 20% alcohol?
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
.2(120+x)=120*.25
24+.2x=30
.2x=30-24
.2=6
x=6/.2
x=30 ml of liquid needs to be added.
.2(120+30)=120*.25
.2*150=30
30=30