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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