Basic Counting Principle The Basic or Fundamental Counting Principle can be used determine the possible outcomes when there are two or more characteristics can vary. Example: Ice cream comes in either a cup or a cone and the flavors available are chocolate, strawberry and vanilla. ``` / chocolate cup / chocolate < / \ chocolate cone / / / strawberry cup <-- strawberry < \ \ strawberry cone \ \ / vanilla cup \ vanilla < \ vanilla cone``` The diagram above is called a tree diagram and shows all of the possibilities. The tree diagram could also be arranged in another way. Both diagrams have 6 total outcomes. ``` / chocolate cup / / cup <-- strawberry cup / \ / \ vanilla cup / < \ \ / chocolate cone \ / \ cone <-- strawberry cone \ \ vanilla cone ``` To determine the total number of outcomes, multiply the number of possibilities of the first characteristic times the number of possibilities of the second characteristic. In the example above, multiply 3 times 2 to get 6 possible outcomes. If there are more than two outcomes, continue to multiply the possibilities together to determine the total outcomes. Return to Top

#### Find the Total Possible Outcomes

Outcomes =