If A and B are two events such that P(A)+P(B)-P(AandB)=P(A) , then ?

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1 Answer
Sep 26, 2017

P(A|B)=1

Explanation:

we have

P(A)+P(B)-P(AnnB)=P(A)

=>P(B)-P(AnnB)=0

=>P(B)=P(AnnB)

=>1=(P(AnnB))/(P(B))

but

(P(AnnB))/(P(B))=P(A|B)

:.P(A|B)=1