If $A$ and $B$ are two related events, and $P(A \mid B)$ represents the conditional probability, Bayes’ theorem states that

- $P(A\mid B) = \dfrac{P(A)}{P(B)} P(B\mid A)$
- $P(A\mid B) = P(A) P(B) P(B\mid A)$
- $P(A\mid B) = \dfrac{P(A)}{P(B)}$
- $P(A\mid B) = P(A)+P(B)$