Probability · Classes 11, 12

Bayes Theorem

Bayes theorem requires P(B)>0.

FORMULA
\(P(A|B)=\frac{P(B|A)P(A)}{P(B)}\)

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Worked example

P(B|A)=0.8,P(A)=0.2,P(B)=0.4 ⇒ 0.4

Understand this formula

Bayes theorem requires P(B)>0.

Check measurement units, mathematical domains and rounding before applying any result in an examination.

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