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what is the meaning of mutually exclusive events
In logic and probability theory, two events are mutually exclusive or disjoint if they cannot both occur at the same time
what is an example of mutually exclusive events
An example of mutually exclusive events is the set of outcomes of a single coin toss, which can result in either heads or tails, but not both.

Question: when was the theory developed
Self-contained rewrite: when was probability theory developed