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 LordRaaa May 15th, 2012 01:49 AM

Formula help

I've got this equation for blood alcohol content, and I need to find the BAC at certain times.

BAC equation:

B = (A/rW) * 100 - V t
B

where B = Bac, A is amount of alcohol in grams, r = 0.7, W is mass in grams, V is 0.015 and t is time since drinking.

I have to find bac with mass 75000 grams (75kgs), 50 grams of alcohol after 5 hours. I subbed it all in and the answer is 0.02, which is fine.

My question is, I need to find how long will it take for the BAC to be below 0.05 in the above question.

Thank you.

 LordRaaa May 15th, 2012 01:50 AM

Re: Formula help

Would it just be setting b = 0.05 and solving for t?

I tried that and got 2.4

 Denis May 15th, 2012 05:56 AM

Re: Formula help

Lordy, lordy...can you post your problem again, paying attention to Capitals and lowercase;
like, A and a would be 2 DIFFERENT variables :idea:

 skipjack May 15th, 2012 10:01 AM

Presumably, BAC means "blood alcohol concentration".

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