Exercise 1 Page 961

Events that cannot occur at the same time are mutually exclusive. Mutually exclusive events have no outcomes in common. For example, because it is not possible to toss a coin and obtain heads and tails at the same time, these two events are mutually exclusive.

Addition Rules for Probability
If $A$ and $B$ are mutually exclusive events, the probability that $A$ and $B$ will occur is $P (A and B) = 0 .$	If $A$ and $B$ are not mutually exclusive events, the probability that $A$ and $B$ will occur is $P (A and B) \neq = 0 .$

Let $A$ be getting a jack card and $B$ be getting a club card from a standard deck of cards.

There are four jacks in the deck and one of them is a club, so it is possible to be both a jack and a club. Therefore, $A$ and $B$ are not mutually exclusive events.