The concentration of alcohol in alcoholic drinks is “proof”. The proof is twice the alcohol by percent. For example, an 80-proof whiskey has 40% alcohol by volume. How many milliliters (ml) of alcohol are in a 44.3ml (1.5oz) shot of 90-proof whiskey?
The Correct Answer and Explanation is:
To calculate the volume of alcohol in a 44.3 ml (1.5 oz) shot of 90-proof whiskey, we need to use the information that “proof” is twice the alcohol by percentage. This means that a 90-proof whiskey contains 45% alcohol by volume.
Step 1: Understand the proof-to-alcohol ratio
Since 90-proof whiskey is twice the alcohol percentage, we can find the percentage of alcohol by dividing the proof by two: Alcohol percentage=Proof2=902=45%\text{Alcohol percentage} = \frac{\text{Proof}}{2} = \frac{90}{2} = 45\%Alcohol percentage=2Proof=290=45%
So, the whiskey contains 45% alcohol by volume.
Step 2: Convert alcohol percentage to volume
To determine the volume of alcohol in the shot, we multiply the total volume of the drink by the percentage of alcohol: Alcohol volume=Total volume×Alcohol percentage100\text{Alcohol volume} = \text{Total volume} \times \frac{\text{Alcohol percentage}}{100}Alcohol volume=Total volume×100Alcohol percentage
Substitute the values: Alcohol volume=44.3 ml×45100=44.3 ml×0.45=19.935 ml\text{Alcohol volume} = 44.3 \, \text{ml} \times \frac{45}{100} = 44.3 \, \text{ml} \times 0.45 = 19.935 \, \text{ml}Alcohol volume=44.3ml×10045=44.3ml×0.45=19.935ml
Step 3: Round the result
The volume of alcohol in the 44.3 ml shot of 90-proof whiskey is approximately 19.94 ml.
Explanation:
To calculate the amount of alcohol in the shot, we first converted the proof to the alcohol percentage. Since the proof is twice the alcohol percentage, we divided the proof by two to determine the percentage of alcohol by volume. Then, we multiplied the volume of the shot by the alcohol percentage to find the amount of alcohol. In this case, the 44.3 ml shot of 90-proof whiskey contains about 19.94 ml of pure alcohol.
