Two events A and B are exclusive if they cannot occur together.
For example, if A is the event getting a total of 6 when throwing
two dice and B is getting a total of 9 when throwing two dice
then A and B are exclusive, for they cannot both happen at
the same time. However, if C is the event getting a double
when throwing two dice A and C are not exclusive as both are
possible with a throw of two 3s.
three or more events are such that no two of them can occur
at the same time, they are said to be mutually exclusive.