2. Probability

3. THEORETICAL Theoretical probability can be found without doing and experiment. EXPERIMENTAL Experimental probability is found by repeating an experiment and observing the outcomes.

4. I am going to take 1 marble from the bag. What is the probability that I will pick out a red marble? Theoretical Probability I have three marbles in a bag. 1 marble is red 1 marble is blue 1 marble is green

5. Theoretical Probability Since there are three marbles and only one is red, I have a 1 in 3 chance of picking out a red marble. I can write this in three ways: As a fraction: 1/3 As a decimal:.33 As a percent: 33%

6. Experimental Probability Notice the Experimental Probability of drawing a red, blue or green marble.

7. Simple Probability The probability of one independent event. An independent event is one that does not affect the outcome (or probability) of any other event.

8. Simple Probability

9. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Simple Probability

10. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? Simple Probability

11. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? 4/36 = 1/9 Simple Probability

12. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? 4/36 = 1/9 Simple Probability Example 2: What is the probability of drawing a king from a deck of cards?

13. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? 4/36 = 1/9 Simple Probability Example 2: What is the probability of drawing a king from a deck of cards? 4/52 or 1/13

14. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? 4/36 = 1/9 Simple Probability Example 2: What is the probability of drawing a king from a deck of cards? 4/52 or 1/13 Example 3: What is the probability of drawing a queen of hearts from as deck of cards?

15. probability of an event or P(event) is number of favorable outcomes total number of possible outcomes Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? 4/36 = 1/9 Simple Probability Example 2: What is the probability of drawing a king from a deck of cards? 4/52 or 1/13 Example 3: What is the probability of drawing a queen of hearts from as deck of cards? 1/52

16. Example 1: Sarah rolls two 6-sided numbered cubes. What is the probability that the two numbers added together will equal 5? Simple Probability Example 2: What is the probability of drawing a king from a deck of cards? Example 3: What is the probability of drawing a queen of hearts from as deck of cards?

17. Compound Probability The probability of two independent events If an event is independent, it does not affect the outcome of other events.

18. “OR” P(A or B) = P(A) + P(B) Example: When you flip a fair coin and roll a number cube, what is the P(head or 4)? P(head or 4) = ½ + 1/6 = 3/6 + 1/6 = 4/6 = 2/3

19. Example: Alfred is going to the Lakeshore Animal Shelter to pick a new pet. Today, the shelter has 8 dogs, 7 cats, and 5 rabbits available for adoption. If Alfred randomly picks an animal to adopt, what is the probability that the animal would be a cat or a dog? 8/20 + 7/20 = 15/20 = 3/4

20. “And” P(A and B) = P(A) x P(B) Example: When you flip a fair coin and roll a number cube, what is the P(head and 4)? P(head, 4) = ½ x 1/6 = 1/12

21. Practice 1.P(heads, hearts) = 13/104 2.P(tails, four) = 4/104