1. Aim: What is the counting principle?
Do Now: Multiply.
5 · 6 · · 4 · 3
12 · 5 · 3

2. Vocabulary Tree Diagram – an organized list of all possible outcomes
Lists the sample space
Counting Principle – finds the total number or possible outcomes by multiplying all the possibilities
Example. Tossing a coin and rolling a die
Tossing a coin = 2 possibilities
Rolling a die = 6 possibilities
So: x 6 = 12 total possible outcomes

3. Example
Draw a tree diagram to represent the number of outcomes. Use the counting principle to verify your answer.
Example A quarter is tossed and a die is rolled.

4. Answer

5. Practice
Draw a tree diagram to represent the number of outcomes. Use the counting principle to verify your answer.
Angelino’s restaurant serves lunch with 2 choices for appetizer- soup or salad and 4 choices for main course – pizza, spaghetti, chicken parmesan, and lasagna.