1. NEW UNIT: Samples & Populations
Learning Target: I will calculate measures of center and measures of variability through the mean, median and range.
Pick up SP packet and SP Vocabulary Toolkit
Homework:
1) SP1.1 p. 4 – Mean, Median, and Range & CORRECT w/Zaption video SP 1.1 part 1 2) Kahn Academy Video – MAD 9 min. – Notes!
Warm Up: Review Filling & Wrapping Unit Test & Complete the Cover Sheet with details on results. Retake: This Thursday, April 21, Math Lab

3. Toolkit
p. 3
Variability is the spread of data or how much data points differ from each other.

5. Toolkit
Sample: A group of people or objects selected from a population.

6. Let’s see how finding the Mean, Median, and Range
will help answer that question.

7. The value found when all the data are
Mean - (you “mean” the Average)
The value found when all the data are
combined and redistributed evenly.
To find the mean (average) of any data set, add all the values together and then divide that total by the number of values in the set.
Practice : (Calculator okay )
75, 68, 29, 52, 97, 14, 22
Step 1
Add them together
= 357
Step 2
Divide the total by the number of values
357 ÷7 = 51

8. The number that marks the middle of an ordered set of data.
Median - (Middle)
The number that marks the middle of an ordered set of data.
To find the median, put the data set in order from least to greatest, then find the number right in the middle of the set. (If there is an even number of values in the set, find the average of the two numbers in the middle of the set.)
Practice :
89, 76, 85, 76, 77, 84
Step 1
Put them in order least to greatest.
76, 76, 77, 84, 85, 89
Step 2
Locate the number(s) in the middle of the set
Step 3 (ONLY FOR AN EVEN NUMBER OF VALUES IN THE SET)
Find the average of the two numbers
( )/2 = 80.5

9. Measures of Center: Mean and Median
p. 2
How do you calculate the mean?
…the median?
You mean the “average”
The number that marks the midpoint of an ordered set of data.
Add up all the data
Divide by the number of data
Count the number of data.
The number at the midpoint marks the median. (If there are even numbers, find the mean between the middle two numbers.
Mean: 5, 8, 10, 12, 7
Median: 5, 8, 10, 12, 7
Mean: 50, 45, 37, 40, 45, 60
Median: 50, 45, 37, 40, 45, 60

10. Mean: = ÷ 3 = 80 Mean = 80
Median: 60, 80, Median = 80
Mean: = ÷ 3 = 80 Mean = 80
Median: 75, 80, Median = 80

12. The DIFFERENCE between
Range
The DIFFERENCE between
the maximum value and the minimum value of a set of data.
To find the range of a data set, subtract the minimum value from the maximum value of the set.
Practice in your journal:
89, 76, 85, 76, 77, 84
Step 1: Put the numbers in order to determine
the maximum and minimum values in the set
Step 2
Subtract the minimum value from the maximum value.
76, 76, 77, 84, 85, 89
89 – 76 = 13

13. Measures of Variability: Range and Mean Absolute Deviation
How do you calculate the
range?
Find the difference between the maximum and minimum values.
Range = max – min
Range: 5, 8, 10, 12, 7

14. 1. Determine the range of Jun’s test scores. (80, 60, 100)
1. Determine the range of Jun’s test scores (80, 60, 100). Show your calculations. B.
3. Determine the range of Mia’s test scores (75, 80, 85).

15. Mia’s results are more consistent and Jun’s are more variable.
5. Use the measures of spread you found in parts 1 and 2. Compare Jun’s and Mia’s test performances. Write at least two complete sentences.
Mia’s results are more consistent
and Jun’s are more variable.
Overall, Mia’s performance is more successful than Jun’s if success is judged on
how consistently each student performs.

16. NEW UNIT: Samples & Populations
Did I reach my Learning Target? I will calculate measures of center and measures of variability through the mean, median and range.
Homework:
1) SP1.1 p. 4 – Mean, Median, and Range & CORRECT w/Zaption video SP 1.1 part 1 2) Kahn Academy Video – MAD - 9 min – Take Notes!