- 42% teen smoke cigarettes
- 53% of all smokers are female
- 45% of all non-smoker are female
- What the probability of selecting a female, and she doesn’t smoke
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I certainly hope these figures are way too high! It's an expensive
and dirty addiction that makes your breath and whole body stink,
and if you get trapped for a long time in a place where you can't
smoke, you're absolutely miserable. And quitting is hell! I'm
speaking from experience! I no longer smoke, and I'd give anything
if I'd never started. I know what I'm talking about, so don't get addicted!
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Anyway, here's the problem:
42% are smokers, so 58% are nonsmokers. 45% of those 58% who
are nonsmokers are the nonsmoking females. That's (.45)(.58)=.261
That's the probability of selecting a nonsmoking female.
[Notice that the "53% of all smokers are female" is not needed
and has no effect of the problem for all it does is tell about
how the smokers are distributed between the sexes, but we are only
interested in the 58% who are nonsmokers].
Edwin