Hello, I was hoping somebody can guide me with this problem, or perhaps help walk me through it. Its for a stats (probability theory) class.(adsbygoogle = window.adsbygoogle || []).push({});

The question reads:

-- Suppose that the probability of exposure to the flu virus during flu season is 0.3. People can get a flu vaccine wich prevents the vaccinated person getting the flu, if exposed, in 80% of cases. People who are not vaccinated get the flu 90% of the time if they are exposed to the virus. Suppose that two friends, Scott and Kevin spend flue season in different places and are not in physical contact with the same people. Scott received the flu vaccine but Kevin did not.

a) what is the probability that at least one of these two get the flu?

b) if at least one of the did get the flu, what is the probability it was kevin.

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Yes, this problem is very tricky.

What I initally tired to do was figure out the probability that kevin and scott got the flu, but that didn't work.

I thought of finding A u B where A is the probability that scott go the flue and B the probability that kevin got it. A u B is the probability that at least one of them gets it.

Can somebody please help me with this.

Thanks

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# Homework Help: Probability theory problem

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