1. Lesson 1 Exploring Measures of center and spread
Algebra 1
Lesson 1
Exploring Measures of center and spread

2. Warm up Find the mode, median and mean of these data.
8, 4, 16, 8, 12, 19, 35, 8, 4, 11

3. Definitions Mode – value or values that occur most often.
Mean – the sum of the values in the set divided by the number of values in the set.
Median – the middle value in a set when the values are arranged in numerical order.

4. To find the mode Arrange the data in order.
Look at each data to determine the most frequent value.

5. To find the median
Arrange the data in ascending order, from small to big
Find the number in the middle or find the average of the 2 middle numbers

6. To find the mean Add all the numbers in the set.
Divide the total with the number of data values

7. Example 1 Find the mean and median of each data set.
b. 75, 97, 360, 84, 119, 100

8. Example 2
Caleb and Kim have bowled 3 games.
Their scores are shown below.
Name
Game 1
Game 2
Game 3
Average Score
Caleb
151
153
146
Kim
122
139
189
Houghton mifflin harcourt algebra 1 vol 1 p 377
Complete the table. How do you find the average of their scores?

10. Explore the data How do their average scores compare?
Who’s game is more consistent?
Is Caleb’s scores farther from or closer to the average than Kim’s?

11. They bowl a fourth game, where Caleb scores 150 and Kim scores a 175
They bowl a fourth game, where Caleb scores 150 and Kim scores a 175. How does this affect
a. Caleb’s average?
b. Kim’s average?

12. 4. Does the Game 4 score affect the consistency of their scores
4. Does the Game 4 score affect the consistency of their scores? Explain.

13. Conclusion
1. Is the average an accurate representation of Caleb’s bowling?
2. Is the average an accurate representation of Kim’s bowling?

14. A1 Find the mean and the median of each data set:
1. The numbers of hours Cheri works each day are 3, 7, 4, 6, and 5

15. 2. Find the mean and the median .
The weights of 6 members of a basketball team are 125, 136, 150, 119, 150, and 143.

16. 3. Find the mean and the median of 36, 18, 12, 10, and 9

17. Reflections
How do you find the mode, median and mean of a set of data.