3.  Theoretical probability shows what should happen in an experiment.  Experimental probability shows what actually happened.

4. Experimental probability: P(event) = number of times event occurs total number of trials Theoretical probability: P(A) = number of favorable outcomes total number of possible outcomes

5.  A bag contains three red marbles and three blue marbles. P(red) = 3/6 =1/2 Theoretical (The result is based on the possible outcomes) Not in notes

6.  You draw a marble out of the bag, record the color, and replace the marble. After 6 draws, you record 2 red marbles P(red)= 2/6 = 1/3 Experimental ( The result is found by repeating an experiment.) Not in notes

7. 1. P (heads) =________ 2. P (tails) = ________ HEADSTAILS llll llll llll llll llll llll llll Experimental =_________________ =__________________ Theoretical 15 35 20 35 4 7 3 7 1 2 1 2

8. Experimental - Theoretical This is about 7% 1 14 Tails? 1 14

9. 4) P(4) = ______________ 5) P(odd ) = __________ 6) P(2 or 5) = __________ 7) P(factor of 3) = _________ David rolled a number cube, with the numbers 1-6 on it. He recorded the results in the table below. NumberOutcomes 1 IIII 2 III 3 IIII 4 IIII I 5 II 6 I 8) What is the difference between the experimental probability of rolling a 2 or 5, and the theoretical probability of rolling a 2 or 5? 1/6 10/20 = ½ 5/20 = 1/4 8/20 = 2/5 1/3 – 1/4 = 4/12 – 3/12 = 1/12 6/20= 3/10 Experimental Theoretical 1/2 1/3 1/3

10. If a car factory checks 360 cars and 8 of them have defects, how many will have defects out of 1260? P(defects) = 8 360 = 1 45 1 = 1260 X = = 281260 ÷ 45 9)

11. Essential Question How are experimental and theoretical probability alike?

12. Date __________________________

13. probability shows what __________________ in an experiment. probability shows what _________________.

14. Experimental probability: P(event) = ___________________________ Theoretical probability: P(A) = _____________________________ _

15. 1. P (heads) =________ 2. P (tails) = ________ HEADSTAILS llll llll llll llll llll llll llll Experimental =_________________ =__________________ Theoretical

16. Experimental - Theoretical

17. David rolled a number cube, with the numbers 1-6 on it. He recorded the results in the table below. NumberOutcomes 1 IIII 2 III 3 IIII 4 IIII I 5 II 6 I 4) P(4) = ______________ 5) P(odd ) = __________ 6) P(2 or 5) = __________ 7) P(factor of 3) = _________ What is the difference between the experimental probability of rolling a 2 or 5, and the theoretical probability of rolling a 2 or 5? Experimental Theoretical 8)

18. If a car factory checks 360 cars and 8 of them have defects, how many will have defects out of 1260? P(defects) = 9)

19. Essential Question How are experimental and theoretical probability alike?