Stem and Leaf Plots
Definitions- Range

Range- The difference between the
greatest and least numbers in a data set
Data set: 23, 45, 60, 55, 80, 75, 15
Largest number: 80
Smallest number: 15
Difference: 80-15= 65
More on Range
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Range is not a measure of central
tendency.
It is a measure of variation…..it
describes the spread of the data.
Stem and Leaf Plots
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What is a stem and leaf plot?
It is a way to represent specific data.
It organizes data so it can be analyzed visually and mathematically
When is it appropriate to use a stem and leaf
plot?
When data can be grouped into intervals (stems) and the data values
within the intervals can be plotted as the leaves.
Stem and Leaf Plots
Parts of stem and leaf plots
Stem
Leaf

Stem and Leaf Plots
In a Stem and Leaf Plot, the data are organized from least to
greatest. The digits of the greatest place value usually form the
Stems, the next place value of digits form the leaves.
Stem and Leaf Plots
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How do we create them?
We start with a data set
All data should be in order from least to
greatest.
Each stem and each leaf must be
represented.
Always list the digit even if it is repeated
Data set

Use the
following
data set to
create a
stem and leaf
plot
Chick Weight (grams)
19
11
21
20
6
13
12
21
7
18
5
11
10
25
12
12
Stem and Leaf Plots

Step 1: Create the graph
Stem and Leaf Plots
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Step 2:
Choose the
stems using
digits in the
tens place
What are the stems? (digits in the tens place)
19 6 7 10
11 13 18 25
21 12 5 12
20 21 11 12
0, 1, 2
The least value is 5, it has a 0 in the tens place
The greatest value is 25, it has a 2 in the tens place
Stem and Leaf Plots
Step 3: List the stems in order from
least to greatest.
Stems: 0, 1, 2

0
1
2
Stem and Leaf Plots

Step 4: Order the leaves – least
to greatest
0
567
1
011222389
2
0115
19 6 7 10
11 13 18 25
21 12 5
12
20 21 11 12
Always write each
leaf even if the data
repeats
Completing Graph

What do we always do before
completing a graph?????????????
Making Inferences

When you analyze data, you can make inferences. That
means, we can draw conclusions based on the data.
Making Inferences
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Find the mode ______
Find the range ______
Find the median _____
The stem and leaf
plot shows the
number of miles
Jessie biked each
day during the
month of July.
Miles Jessie biked
Stem
Leaf
0
556
1
00001225889
2
1258
3
0
2|1 = 21 miles
Analyzing Data
What was the least number
of miles Jessie biked in
July? _______
What was the largest
number of miles Jessie
biked in July? _______
How many days did Jessie
bike only 10 miles? ____
Miles Jessie biked
Stem
Leaf
0
556
1
00001225889
2
1258
3
0
2|1 = 21
miles
Make your own graph
Making a stem and leaf plot

Use the data in the following
table to create your own stem
and leaf plot.
Quiz scores in
Coach Bowen’s
Class
70 96 72 91
80 80 79 93
76 95 73 93
90 93 77 91
Does it look like this?
Quiz scores in Coach Bowen’s Class
Stem
7
023679
8
00
9
9|1= 91 on quiz
Leaf
01133356
Answer the questions about your graph
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What is the highest score on quiz? ____
What was the lowest score on quiz?____
What is the mode? ____
What is the median ____
What is the range of the quiz scores? ___
Question
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Can we use stem and leaf plots to
represent all data?
Conclusion: Stem and Leaf Plots
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Are easy to read
Are easy to create
Great graph to display data
Can not be used for all data sets