1. Lesson 6.8 The Counting Principle 1/20/10

2. Tree Diagram - Used to count the number of possibilities Uses branching to list choices

3. A sandwich shop makes egg salad, tuna salad, or tomato salad sandwiches using either wheat or rye bread. Make a tree diagram to count the number of possible sandwich choices. Salad egg tuna tomato Bread wheat rye wheat rye wheat rye 6 different sandwiches are possible.

4. Counting Principle - If one event can occur in m ways, and for each of these ways a second event can occur in n ways, then the number of ways that the two events can occur together is m n. uses multiplication to find the number of possible ways can be extended to three or more events

5. Using the Counting Principle A yogurt shop offers 18 flavors of yogurt, as well as 3 types of cones, and 12 different toppings. Assuming a frozen yogurt is a combination of one cone, one yogurt flavor, and one topping, how many choices are possible? Flavors of yogurt 18 Types of Cones 3 Toppings 12 648 choices

6. Finding a Probability As part of its 20 th anniversary celebration, a museum is offering $20 off an art print to each 20 th visitor to the museum. You visit the museum on Thursday and again on Friday. What is the probability that you receive the $20-off coupon on both days? Probability on Thursday Probability on Friday 1 20 1 20 = 1 400