Section 9 6 Obj Conditional Probability Monday April
Section 9. 6 Obj: Conditional Probability Monday, April 13, 2015 Warm up: What do you think conditional probability is? Consider the two words both separately and together.
Example 1 A chip is selected at random. Find the probability of selecting 2 3 4 5 6 7 A #3, given that a green chip is selected. An even #, given a yellow chip is selected. A red chip, given that an odd number is selected. An odd #, given a red chip is selected. A yellow chip, given that the # selected is at least 5. A green chip, given the # selected is at most 4. 8
Example 2 A bag has 17 blue large marbles, 3 blue small marbles, 8 red large marbles, and 12 red small marbles. P(large) Total P(blue) P(large | red) P(red | large) Total P(small | blue) P(large | blue)
Conditional Probability Fifty-eight percent of the respondents were male. Twenty percent of all respondents were males who said they jog. Find the probability that a male respondent jogs.
P( male ) = 58% P( male and jogs ) = 20% =0. 2 0. 58 Substitute 0. 2 for P(J and M) and 0. 58 for � 0. 344 Simplify.
What can you answer using the tree diagram? 1. 2.
Boys Girls Totals 6 th graders 7 8 7 th graders 6 7 a) P(7 th grade girl) b) P(8 th grade boy) c) P(girl |7 th grade) d) P(6 th – grade | boy) e) P(8 th – grade | girl) f) P (boy |8 th grade) 8 th graders 10 12 Totals
Example 5 – deck of cards R: The card is red K: The card is a King H: The card is a heart 1. P(K |H) 2. P(H |K) 3. P(R |K) 4. P(K |R) 5. P(R |H) 6. P(H |R)
Take a photo and try on your own at home for funzies. Good neat work will receive extra credit! A survey of Pleasanton Teenagers was given. - 60% of the responders have 1 sibling - 20% have 2 or more siblings - Of the responders with 0 siblings, 90% have their own room - Of the respondents with 1 sibling, 20% do not have their own room - Of the respondents with 2 siblings, 50% have their own room Create a tree diagram and determine A)P(own room | 0 siblings) B)P(share room | 1 sibling)
- Slides: 12