What is the Probability of A' n B' Given A' and A, B, and A n B?

[hellokitten]

Given P(A), P(B), and P(A n B) . Find the P(A' n B' | A')
We know P(AuB) = P(A)+P(B)- P(A n B)
Then
P(A' n B'|A') = P(A' n B' n A' ) / P(A') = P(A' n B') / P(A') = P(A u B)' /P(A') = [1-P(A u B) ]/ P(A') =
[1-P(A u B)] / [1-P(A)] Correct?

 

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