1. Warm Up
Problem of the Day
Lesson Presentation
Lesson Quizzes

2. Warm Up
1. A jar contains 6 red, 8 blue, and 10 white marbles. Would you be more likely to pull out a red or a blue marble?
Determine if the event is impossible, unlikely, as likely as not, likely, or certain.
2. Attendance at a city council meeting is at 100%.
Mr. Lloyd is a council member. How likely is it that Mr. Lloyd is at the meeting?
blue
certain

3. The probability of Liana making a free throw was
Problem of the Day
The probability of Liana making a free
throw was 2 3
. If she made 24 of her free
throws, how many did she miss? 12

4. Learn to find experimental probability.

5. Vocabulary
experimental probability

6. Experimental probability is one way of estimating the probability of an event. The experimental probability of the event is found by comparing the number of times an event occurs to the total number of trials. The more trials you have, the more accurate the estimate is likely to be.

8. Additional Example 1: Sports Application
During skating practice, Sasha landed 7 out of 12 jumps. What is the experimental probability that she will land her next jump?
P(event) 
number of times an event occurs
total number of trials
number of jumps landed
number of jumps attempted
P(jumps landed)  7 12 =
Substitute data from the experiment.
The experimental probability that Sasha will land her
next jump is . 7 12

9. “P(event)” represents the probability that an event will occur
“P(event)” represents the probability that an event will occur. For example, the probability of a flipped coin landing heads up could be written as “P(heads).”
Writing Math

10. number of times an event occurs total number of trials
Check It Out: Example 1
During basketball practice, Martha made 9 out of 10 free throws. What is the experimental probability that she will make her next attempt?
P(event) 
number of times an event occurs
total number of trials
P(free throws made) 
number of free throws made
number of free throws attempted 9 10
= = 90%
Substitute data from the experiment and write as a percent.
The experimental probability that Martha will make the
next free throw is or 90%. 9 10

11. Additional Example 2A: Application
Students have checked out 55 books from the library. Of these, 32 books are fiction.
What is the experimental probability that the next book checked out will be fiction?
number of fiction books checked out
total number of books checked out
P(fiction)  32 55 
Substitute data.
The experimental probability that the next book checked out will be fiction is approximately 32 55 .

12. Additional Example 2B: Application
What is the experimental probability that
the next book checked out will be nonfiction?
P(fiction) + P(nonfiction) = 1
Use the complement. 32 55 +
P(nonfiction) = 1
Substitute.
Subtract from both sides. 32 55 32 55 –
P(nonfiction) = 23 55
Simplify.
The experimental probability that the next book checked
out will be nonfiction is approximately 23 55 .

13. number of pears selected
Check It Out: Example 2A
Students have a fruit choice for lunch of an apple or a pear. So far 18 of 47 students have selected pears.
What is the experimental probability that the next fruit selected will be a pear?
P(pear) 
number of pears selected
total number of fruit selected 18 47 
Substitute data.
The experimental probability that the next fruit selected will be a pear is approximately 18 47 .

14. What is the experimental probability that
Check It Out: Example 2B
What is the experimental probability that
next fruit selected will be an apple?
P(pear) + P(apple) = 1
Use the complement. 18 47 +
P(apple) = 1
Substitute.
Subtract from both sides. 18 47 18 47 –
P(apple) = 29 47
Simplify.
The experimental probability that the next fruit selected will be an apple is 29 47 .

15. Lesson Quiz for Student Response Systems
Lesson Quizzes
Standard Lesson Quiz
Lesson Quiz for Student Response Systems 15 15 15

16. Lesson Quiz
1. In a soccer shoot-out, Bryan made 4 out of 9 goals. What is the experimental probability that he will make the next shot?
2. It has rained on the last 2 out of 10 Fourth of July parades in Swanton.
A. What is the experimental probability that it will rain on the Fourth of July parade this year?
B. What is the experimental probability that it will not rain on the Fourth of July parade this year? 4 9 1 5 4 5

17. Lesson Quiz for Student Response Systems
1. During a shot put practice session, Greg crossed the 70-foot mark in 15 out of 21 attempts. What is the experimental probability that he will cross the 70-foot mark in his next attempt? A. B. C. D. 2 7 5 7 6 7 7 5 17 17 17

18. Lesson Quiz for Student Response Systems
2. Simon is practicing basketball. He made 33 of 42 free throws he attempted. What is the experimental probability that we will make his next free throw? A. B. C. D. 9 14 11 42 11 14 14 11 18 18 18

19. Lesson Quiz for Student Response Systems
3. Rachel found that 20 out of 48 cars that entered a parking lot were red. What is the experimental probability that the next car that comes in is red? What is the experimental probability that the next car that comes in is not red? A. B. C. D. 19 19 19