A11­6MeanMedianModeRange.notebook
January 07, 2013
Algebra 1
Ch.1 Notes Page 41
P41 1­6 Mean, Median, Mode, and Range
Measures of Central Tendency
Mean = Average Add and Divide by the number of numbers
Median = Number in the Middle
Put numbers in order and find the middle
Mode = Most
The number that occurs the most in the data
An outlier is a number that does not fit with the rest of the data.
A11­6MeanMedianModeRange.notebook
January 07, 2013
Example
Find the mean, median, and mode of the data in the data below.
8, 2, 2, 6, 8, 4, 4, 8, 6, 2, 6, 8
Example:
Your grades on 3 history exams are 80, 93, and 91.
What do you need on your next exam to have a 90 average?
A11­6MeanMedianModeRange.notebook
January 07, 2013
Range
The range of a set of data is the difference between the highest and lowest value in the set.
Find the Range of each data set.
What does this tell you about the data?
25, 30, 30, 47, 28
34, 28, 31, 36, 31
Stem­and­Leaf Plot
Used to Organize Data so that you can see every number.
The numbers have to be put in order first.
The stems are on the Left and the leaves are on the Right
13, 8, 21, 14, 32, 7, 3, 18, 33, 20, 32, 15
A11­6MeanMedianModeRange.notebook
Two Sided Stem­and­Leaf Plot
January 07, 2013