Measures of Central Tendency

1
Measures of Central Tendency
12, 32, 21, 32, 24, 18, 32, 13, 17, 24, 12
Mode- When given a data set, the mode is the most
frequently appearing number
32 is the mode since it occurs 3 times
12, 32, 21, 32, 24, 18, 32, 13, 17, 24, 12, 12
A data set can have more than one mode
Now 32 and 12 are the modes of the data set.
2
Median
12, 14, 14, 15, 19, 20, 20, 24, 25, 28, 29, 30, 30
The median is the middle number when the numbers
are ordered from least to greatest.
20 is the middle number or median
3
The Meaning of Mean
At the 5th grade level, students learn to
calculate mean by adding up a set of numbers and
then dividing by the number of numbers. For now,
we just want to work on understanding the concept.
Lets take this situation Jake, Sarah, and
Destiny have some cookies. Jake has 7, Sarah has
2 and Destiny has 3.
Destiny
Sarah
Jake
4
The age appropriate meaning of mean for this
group is equal groups.
When Jake shares his 7 cookies, 3 equal groups
can be made. Since each child has 4 cookies, the
mean of 7, 2, and 3 is 4
Students can learn to relate this to the basic
fact of 4 x 3 12
Jake Sarah Destiny
5
Another Way to View Mean
A question could be asked
If 4 kids have a number of pencils and the mean
number of pencils is 3, what possible
combinations could exist?
Think 4 x 312
Here are two possible answers..
Jessica Michelle Devon Alicia
Jessica Michelle Devon Alicia