1. Homework: pg. 446
74.) P(A and B)=0.46*0.32= ) A B.) ) .3142; If A and B were independent, then the conditional probability of A given B would equal the probability of A.

2. 6.3 Tree Diagrams

3. Example 1: Probability of having a certain disease=.05
If you have the disease, probability of testing positive is .98
Probability of false positive is .10
What is the probability that you have the disease if you test positive?

4. Make a Tree Diagram!!! Tested Positive Yes, you have the disease
Tested Negative
Tested Positive
No, you don’t have the disease
Tested Negative

5. Example 2: pg. 446 #72, 73
At a self service gas station, 40% of the customers pump regular gas, 35% pump midgrade, and 25% pump premium gas. Of those who pump regular, 30% pay at least $20. Of those who pump midgrade, 50% pay at least $20. And of those who pump premium, 60% pay at least $20.
What is the probability that the next customer pays at least $20?
What percent of the customers who pay at least $20 pump premium?

8. Homework
Pg. 451 #82-84