Download Measures of Center1

Warm Up for 7/21
What are mean, median, mode, and
range?
 How do you find the measures of
central tendency?

Measures of Central Tendency
Measures of central tendency are numbers
that represent the center of a set of data.
They are averages of the data.
The three most common measures of central
tendency are:
 Mean
 Median
 mode.
What does mean mean?
Mean is the number that represents an equal
distribution of the data.
If each stack was even, how many blocks would be in
each stack? _______
That is what mean means.
What does mean mean?
Mean is the value of each group when the data is
evenly distributed.
That is what mean means.
What is median?
The median is the middle element of a set of data.
The median splits to data into two equal halves.
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
5.5
When there are an even number of elements, the
median is NOT an element in the data set. Rather, it is
the mean of the two middle elements.
What is mode?
Mode is the element of a set of data that occurs
most often.
1, 2, 3, 4, 4, 5, 6, 7, 7, 7, 8, 9, 10
There can be more than one mode.
1, 2, 3, 3, 4, 4, 5, 6, 7, 8, 9, 10
This data is bimodal because it has two modes.
Range
Range is not a measure of central tendency,
rather, it is a measure of the spread of the
data.
Range tells us if the data is clustered or spread
out.
Range is calculated by subtracting the lowest
value (minimum) from the highest value
(maximum).
Range
26, 33, 44, 49, 52, 60, 77, 80
Maximum = 80
Minimum = 26
Range =
54
Class Work


Study Guide workbook section 2-4.
Carefully tear this out and complete #1-6.
Discussion Question
How could measure of central
tendency be used to analyze data?
(i.e. How is knowing this helpful to me?)
Warm Up for 7/23
7, 3, 12, 4, 6, 3, 4, 8, 7, 3, 20




What is the median? How do you find it?
What is the mode?
What is the mean? How do you find it?
What is the range? How do you calculate
it?
Class Work

1.
WS: Study Guide 2-4
Mean = 37.5
Median = 34
Mode = 56
2.
Mean = 7
Median = 6
Mode = 3
3.
Mean = 7.9
4.
Median = 6
Mode = 6 & 7 (bimodal)
Mean = 3
Median = 3
Mode = 3
5.
Mean = 2.8
Median = 2
Mode = 1
Mean = 8.3
Median = 10
Mode = 12
6.
Class Work

Complete the WS: Who’s the Best? by
calculating and comparing the measures and
central tendency and range for each player’s
scores.
Review
1.
2.
3.
4.
5.
What are three measures of central
tendency?
Why are they called “measures of central
tendency”?
How are measures of central tendency
used?
How are measures of central tendency
calculated?
What is one measure of spread?
Homework Check ~
pg. 71 #4-9
4.
5.
6.
7.
8.
9.
Mean = 9, median = 7, mode = 7, 14
Mean = 52.3, median = 57, mode = 59
Mean = 44.6, median = 44, mode = 44
Mean = 8.2, median = 8, mode = 7
Mean = 3.1, median = 2.5, mode = 2
All three are good, however the mean is higher
than most of the data. Median and mode are better
measures of central tendency.
What does mean mean?
That is what mean means.
Homework Check~
Pg. 72 #10-13
10.
Mean = 65.6
Median = 65
Mode = none
11.
12.
Mean = 92.7
Median = 91.5
Mode = 90
13.
Mean = 8.7
Median = 9.0
Mode = 8.0 & 9.3
(bimodal)
Mean = $12
Median = $9
Mode = $6
Warm Up

What is the mean of this data?
1 2 6 3 2 4 3 5

What does mean mean?