If we are dealing with the occurrence of more than one event or activity and they are mutually exclusive, sometimes it is important to be able to determine how many possible outcomes exist. Events are mutually exclusive if they do not effect each other and cannot occur at the same time. The counting principle helps us to determine the amount of outcomes of independent events:
If there are m ways for one activity to occur, and n ways for a second activity to occur, then there are m*n ways for both to occur.
Throw a die and flip a coin.