1 / 17

Splash Screen

Splash Screen. Ch. 8 Probability (P. 374-375). Vocabulary. Probability: a ratio that compares the number of favorable outcomes to the number of possible outcomes. P (event) = number of favorable outcomes number of possible outcomes

Splash Screen

An Image/Link below is provided (as is) to download presentation Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

1. Splash Screen

2. Ch. 8 Probability (P. 374-375)

3. Vocabulary Probability: a ratio that compares the number of favorable outcomes to the number of possible outcomes. P (event) = number of favorable outcomes number of possible outcomes Probability can be expressed as a fraction, a decimal, or a percent.

4. Vocabulary For example: a bag contains 4 red marbles and 3 blue marbles and 3 yellow marbles. The probability of picking the blue marble is 3 (we want to pick blue marbles, so the # of blue marbles are favorable outcomes) 10 (together there are 4(red) + 3(blue) + 3(yellow) = 10 marbles in the bag, so the # of possible outcomes are 10) We express that as P (blue) = 3/10 If the question is find the probability of red or blue marbles: P (red or blue) = 4+3 / 10 = 7/10 *Probability of an event will happen is between 0 and 1. 0 = impossible to happen 1 = certainly will happen An event has higher or lower probability if its closer to 1? Higher An event has higher or lower probability if its closer to 0? Lower

5. Example 1-1a A bag contains 5 blue marbles, 10 red marbles, and 10 yellow marbles. A marble is picked at random. What is the probability the marble is yellow? There are 5 + 10 + 10 or 25 marbles in the bag. There are 10 yellow marbles out of 25 marbles. Answer: The probability the marble is yellow is 2/5. The probability can also be written as 0.4 or 40%.

6. Answer: Example 1-1b A bag contains 3 green marbles, 7 purple marbles, and 15 black marbles. A marble is picked at random. What is the probability the marble is black? (It can also be written as a decimal and percent

7. There are 5 blue marbles out of 10 red marbles. Answer: The probability the marble is blue is The probability can also be written as 0.6 or 60%. Example 1-2a A bag contains 5 blue marbles, 10 red marbles, and 10 yellow marbles. A marble is picked at random. What is the probability the marble is blue or red?

8. Answer: Example 1-2b A bag contains 3 green marbles, 7 purple marbles, and 15 black marbles. A marble is picked at random. What is the probability the marble is green or purple?

9. Example 1-3a A bag contains 5 blue marbles, 10 red marbles, and 10 yellow marbles. A marble is picked at random. What is the probability the marble is white? Answer: Since there are no white marbles, the probability is 0.

10. Example 1-3b A bag contains 3 green marbles, 7 purple marbles, and 15 black marbles. A marble is picked at random. What is the probability the marble is red? Answer: 0

11. There are 9,500 listed phone numbers. Answer: The probability that the phone number you are looking for is listed is Example 1-4a PHONE LISTINGS One town has 10,000 phone numbers in use. Of these, 500 are not listed in the local phone book. What is the probability that the phone number you are looking for is listed in the phone book? 10,000 – 500 or 9,500 phone numbers are listed.

12. Answer: Example 1-4b SCHOOLATTENDANCEOakdale Junior High School has a total enrollment of 670 students. Of these, 45 are absent today. Suppose a student’s name is picked at random. What is the probability that the student picked is absent today?

13. Ch. 8-5 Probability of Compound Events (P.396-397)

14. Vocabulary Compound event: consists of two or more simple events. The probability of compound event can be found by multiplying the probability of two independent events. (Independent event means the outcome of one event does not affect the other event) P(A and B) = P(A) x P (B)

15. Example 5-1a The two spinners below are spun. What is the probability that both spinners will show a number greater than 6?

16. Answer: Example 5-1a

17. Answer: Example 5-1b The two spinners below are spun. What is the probability that both spinners will show a number less than 4?

More Related