If events $A$ and $B$ satisfy $P(B)
eq 0$, which expression correctly…

Question

If events $A$ and $B$ satisfy $P(B)
eq 0$, which expression correctly defines the conditional probability of $A$ given $B$?

Accepted Answer

A. $P(A/B)=\dfrac{P(A\cap B)}{P(B)}$

By definition, conditional probability of $A$ given $B$ is the probability that both $A$ and $B$ occur, restricted to the cases where $B$ has occurred. Hence $P(A/B)=\dfrac{P(A\cap B)}{P(B)}$.

Answer

$P(A/B)=\dfrac{P(A\cup B)}{P(B)}$

Answer

$P(A/B)=\dfrac{P(A)}{P(B)}$

Answer

$P(A/B)=P(A\cap B)\cdot P(B)$

If events $A$ and $B$ satisfy $P(B)\neq 0$, which expression correctly defines the conditional probability of $A$ given $B$?