HI guys,(adsbygoogle = window.adsbygoogle || []).push({});

I was wondering how do find P(A|B)

To calculate the following.

P(A|B) = P(B|A)P(A) / (P(B|A)*P(A) + P(B|A')*P(A'))

I know that

P(B'|A) = .001

P(B|A') = 0.09 and

P(A') = .99

P(A) = .01

and P(B'|A') = .91

I'm pretty sure that it requires the use of P(B'|A) = .001 but I can't seem to understand the relationship.

Could some one please point me in the right direction.

regards

Brendan

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# Finding P(A|B)

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