1. Answers
1. 3/ / / / / /15

2. Section 2-4: Computing Probabilities Using Equally Likely Outcomes
CFU Use a variety of counting methods to … determine probabilities

3. What We Have Done… Basic Probability Permutations/Combinations
N(E)/N(S)
Permutations/Combinations
Now we are just putting them together!
We will use permutations and combinations to fill in our N(E) and N(S) spots!

4. Hints Fill the denominator in first!
Remember that how many we are choosing on the top needs to equal how many we are choosing on the bottom
Sometimes, the problem won’t say all of the ones which get picked, so think through the story in order to make sure it works.

5. Sample Problems
A 12-unit apartment building has 9 smoke alarms which pass inspection and 3 which do not. If 3 smoke alarms are selected at random and tested, what is the probability that they will all pass inspection?
What is the probability that exactly 2 pass inspection?

6. Sample Problems
A total quality management team contains 8 people: 5 from customer service and 3 from data processing. Two team members are selected at random to make a presentation. What is the probability that exactly 1 member is selected from customer service?

7. Sample Problems
A student has 5 coins – 2 dimes and 3 quarters – and 2 coins are selected simultaneously and at random. Find the probability that both are quarters.
Find the probability that at least 1 is a dime.

8. Sample Problems
Sam and Sally are members of a committee containing 4 men and 3 women. A subcommittee of 3 people is going to be chosen from the group. What is the probability that both Sam and Sally will be included?
What about only one of them?

9. Classwork/Homework Worksheet Homework Quiz Wednesday
Chapter 2 Test will be on *Friday*

10. Classwork/Homework Worksheet and p. 60 #9, 11, 13, 15, 17
Homework Quiz Tomorrow
Chapter 2 Test will be on Thursday

11. Sample Problems
An accounting firm regularly audits 4 firms each year. It has 4 chief auditors who direct these audits and the assignment of the chief auditors is at random. What is the probability that all 4 auditors will be assigned to the same firm they were assigned to last year?