1. AP Statistics: Chapter 8 Intro.

2. You come to class totally unprepared for a quiz (imagine that!!!). The quiz consists of 10 multiple choice questions with 5 possible answers. Since you are completely unprepared, you simply randomly fill in answers on the Scan Tron sheet without even reading the questions. Do this at the right.

4. What is P(get a particular question correct) = _______ How many questions would you expect to get correct? _______

5. Let the random variable X represent the number of questions you get correct and complete this probability distribution.

6. To find the probabilities, let’s do a simulation: Each of you do 10 simulations.

7. 0 1 2 3 4 5 6 7 8 9 10

8. We can also find these probabilities theoretically. P(0) is fairly straight forward. ___________

9. For the P(1), P(2), etc., we need to consider all the different ways we can 1 correct or two correct, etc. To determine the number of ways of arranging k successes in n observations we can use the following formula:

10. TI83/84: MATH PRB 4:! 8!=

11. TI83/84: MATH PRB 3: nCr (note: put in n, then do nCr then put in r)

12. P(1) = ___________________ P(2) = ___________________ P(3) = ___________________ P(4) = ___________________ P(5) = ___________________

13. If you need 60% to pass the quiz, what is P(at least 6 questions correct)?

14. Probabilities such as these can be found very easily using the BINOMIAL Distribution.