To get the proof of the alcoholic beverage you multiply the percent By 200.
So an alcoholic beverage that is 80% alcohol is:
.80 x 200 = 160.00 proof or 160 proof
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To get the percent of an alcoholic beverage you take the proof and divide by
200.
So an alcoholic beverage that is 160 proof is:
160/200 = 4/5 = .80 or 80%
A simpler way would be to divide the proof by 2.
160/2 = 80
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40% alcohol is 80 proof. It can get you drunk easily.