# Conditional probability
Last edited: 2024-02-20
Conditional probability
For two events $A$ and $B$ the conditional probability of $A$ happening given $B$ has happened is
$$\mathbb{P}[A \vert B] = \frac{\mathbb{P}[A \cap B]}{\mathbb{P}[B]}.$$Last edited: 2024-02-20
For two events $A$ and $B$ the conditional probability of $A$ happening given $B$ has happened is
$$\mathbb{P}[A \vert B] = \frac{\mathbb{P}[A \cap B]}{\mathbb{P}[B]}.$$