1. 3.3: The Addition Rule Objective: To use the addition rule to calculate probabilities CHS Statistics

2. Warm-up: Something to Consider… Suppose there are 300 students in the 11 th grade. Fifty-five students are taking French, 54 are taking German, and 9 are taking both French and German. What is the probability of selecting one of these students and he/she is taking French or German?

3. Mutually Exclusive Two events are mutually exclusive if they cannot occur at the same time. For example, a person being a male or female cannot occur at the same time. These events are mutually exclusive. However, a person being a male or basketball player can occur at the same time. There can be male basketball players. These event are NOT mutually exclusive. Can you think of other examples of mutually exclusive events?

4. Addition Rule Addition Rule for mutually exclusive (ME) events: P(A or B) = P(A) + P(B) Addition Rule for non-mutually exclusive (NME) events: P(A or B) = P(A) + P(B) – P(A and B)

5. Examples of ME Vs. NME Events: Decide if the following sets of events are mutually exclusive: Event A: Roll a 3 on a die Event B: Roll a 4 on a die Event A: Randomly select a male student Event B: Randomly select a basketball player Event A: Randomly select a blood donor with type O blood. Event B: Randomly select a female blood donor

6. Standard Deck of Cards (52 total cards) 4 Suits (13 Diamonds, 13 Hearts, 13 Spades, 13 Clubs) 4 of each card (A, K, Q, J, 10, 9, 8, 7, 6, 5, 4, 3, 2) 2 Colors (26 Black cards, 26 Red cards) 26 Black: 13 Spades 13 Clubs 26 Red: 13 Diamonds 13 Hearts

7. Addition Rule Examples: 1.You select a card from a standard deck. Find the probability that the card is a 4 or an ace. 2.You roll a die. Find the probability of rolling a number less than three or rolling an odd number.

8. Addition Rule Examples (cont.): 3.A die is rolled. Find the probability of rolling a 6 or an odd number. 4.A card is selected from a standard deck. Find the probability that the card is a face card or a heart.

9. Probabilities Using Tables A blood bank catalogs the types of blood, including positive or negative. Find the probability that the donor has type O blood. Find the probability that the donor has type O or type A blood. Find the probability that the donor has type B blood or is negative. Find the probability that the donor has type O blood or is positive.

10. Probabilities Using Tables (cont.) People aboard a ship that sunk: You randomly select a person on the same model of ship and route. Using the table above, what is the predicted probability of: P(man) = P(man or a boy) = P(man or someone who survived) = P(women or someone who died) =

11. Assignment: pp. 132 – 133 # 1-4, 11 – 22, 25 – 26, 28