A= the paitent is ill: P(A)=0,001

A*= the paitent is not ill

B= the diagnos shows ill

B*=the diagnos shows not ill

given: p(B|A)= 0,8

p(B*|A*)= 0,9

Question: What the probability that the paitent is ill and the diagnos shows ill?

started with: P(A|B)= P(A∩B)/P(B)= (P(A)xP(B|A))/P(B)

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