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Algebra - Blood Alcohol Content (BAC).
Test Yourself 1 - Solutions.


 

For the following questions, you will need one of the following formulae:

where N is the number of standard drinks

 

Finding BAC only. 1.
Number of standard drinks
White wine Red wine
Small glass Large glass Small glass Large glass
0.9 1.4 1.0 1.5

A woman weighing 62 kg drinks three small glasses of white wine and two large glasses of red wine between 8 pm and 1 am.

What would her bloood alcohol content (BAC) be at 1 am? (answer correct to 3 decimal places).

Answer.BAC = 0.057.
  2. Charlotte weighs 55 kg and she consumed 4 standard drinks in the past three hours. She then left but was stopped by the police for a random breath test shorthly after.

What was Charlotte's blood alcohol content (BAC)?

Answer.BAC = 0.051.
  3.
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  5.
Finding number of standard drinks only. 6. 10 grams of alcohol in one standard drink. Answer.10 grams in 1 standard drink.
  7. Georgia weighs 62 kg. She has been drinking for three hours and registers a blood alcohol reading of 0.08.

How many standard drinks had Georgia consumed? Answer.5 standard drinks (4.978).
 

8. (i)

(ii)

  9.
  10.
Finding hours of drinking only. 11. Ben weighs 70 kg and has bought a six-pack of an alcoholic beverage to drink at a party. Each drink in the pack is the equivalent of one standard drink.

What is the minimum length of time over which Ben must consume all six drinks if he is to stay below the 0.05 level of BAC at the end of the party?
(answer to the nearest quarter of an hour).
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Finding time before BAC is below the threshold. 16. Earliest time is 11:20 am.
 

17.

Rosey's BAC would be 0.11
so 7 hours 15 min.
 

18. As noted elsewhere, the relationship between time to derease BAC and the value of BAC in one's blood is linear. Hence there is a constant decrease for any given time interval.

(i) Ben has to decrease his BAC from 0.07625 to 0.05. So:

Ben could start driving at 12:45 am - but he waited until 1:00 am to be safer.

(ii) Yes Ben still had his friends - they waited for him as it wasn't too late.
  19.
  20.
Combination questions.

21. (i)

(ii)

  22. Shane, who weighs 80 kg, consumes five cans of an alcoholic beverage in two hours. Each can contains the equivalent of 1.5 standard drinks.

(i) What is Shane's blood alcohol content (BAC) at the end of 2 hours (answer to 2 significant figures)?

(ii) The formula can be used to estimate approximately how long it will take for a person's blood alcohol content (BAC) to reach zero. How long will it take Shane to reach zero.

 
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