When two events $A$ and $B$ have overlapping outcomes, it might also be of interest to analyze the event of $A$ AND $B$ happening. The combined event of $A$ AND $B$ happening is called the intersection of $A$ and $B$.

Intersection

Definition

The intersection of two events $A$ and $B$ is the set of outcomes that are classified as $A$ AND classified as $B$.

The intersection of $A$ and $B$ is denoted as $A \cap B$.

Take note that two events that are mutually exclusive have zero outcomes that overlap. The intersection of such two events is therefore empty.

The intersection of $A$ and $B$ is the set of outcomes that $A$ and $B$ have in common, which in this case are the outcomes $2$ and $4$:

$A \cap B = \{2, 4\}$

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