For any two events A and B, with \(\mathbb{P}(B) > 0\), we define the conditional probability of A given B (\(\mathbb{P}(A|B)\)) as
\[\mathbb{P}(A|B) = \frac{\mathbb{P}(A \cap B)}{\mathbb{P}(B)}\]
Example: We throw a dice once, and it lands on an even number.