Notes
Name: __________________________________
Date: ______________________ Period: ______
Displaying Data
I. Representing Data
Question #1: Why do we represent data using charts and graphs? ________________________________
Question #2: What does “display” mean? ___________________________________________________
Question #3: What does “frequency” mean? _________________________________________________
Question #4: What does “continuous” mean? ________________________________________________
Question #5: What does “noncontinuous” mean? _____________________________________________
A. Circle Graph

A ________________ ___________________ is a circular chart that is divided into parts so
that the relationship of each part to the whole is clearly shown. It is also called a ___________
________________.
o Here is are two examples of circle graphs:
*We use circle graphs to display percentages (or parts of a whole.)
B. Box-and-Whisker Plot

A __________________________ _______________ is a graph that represents the minimum,
maximum, the median, the first quartile, and third quartile of a data set. Remember that a boxand-whisker plot breaks data down into four equal quartiles. Each quartile is 25% of the data.
o
Here is an example of a box-and-whisker plot:
——|——|——|——|——|——|——|——|——|——|——|——|——|——|——|——|——|
25 30
35 40 45 50 55 60 65 70 75 80 85 90 95 100 105
*We use box-and-whisker plots for two purposes:
1) organizing a large set of data into four equal parts (quartiles) so that it’s easier to
understand
2) comparing two sets of data (especially when they have the same mean or average)
C. Stem-and-Leaf Plot

A _____________________________ ______________ represents numerical data by using the
greatest common place value as the stem and the remaining digits as the leaves.
o
Here is an example of a stem-and-leaf plot from the following data set:
45, 70, 43, 45, 32, 42, 40, 40, 35, 50, 40, 35, 61, 48, 35, 32, 50, 36, 50, 40
32, 32, 35, 35, 35, 36, 40, 40, 40, 40, 42, 43, 45, 45, 48, 50, 50, 50, 61, 70
Stem
Leaf
3
2 2 5 5 5 6
4
0 0 0 0 2 3 5 5 8
5
0 0 0
6
1
7
0
Key: 3|2 = 32
*We use stem-and-leaf plots for organizing lots of numbers (a large set of data) so that they are
easier to understand.
To draw a stem-and-leaf plot, you will need to:
1) Rearrange the data in order from least to greatest.
2) Determine what the stem is and what the leaves are. (The leaf is usually the last digit of the
number, and the stem is all the other digits. All the numbers in the stem must have the same
place value!)
3) Draw the stem-and-leaf plot.
4) Don’t forget to include the key (explaining how to read the stem-and-leaf plot).
Examples
Directions: Use each set of data to make a stem-and-leaf plot.
Ex) 15, 22, 25, 10, 15, 28, 18, 5, 7
Ex) 785, 785, 776, 772, 792, 788, 761, 768
D. Bar Graph

A ________________ ___________________ is a graph that uses vertical or horizontal bars of
different lengths. The length of each bar is proportional to the value it represents.
o

Here are four examples of a bar graph:
You can have 3d bar graphs.
You can have horizontal bar graphs too.
You can have double bar graphs that compare two sets of data at the same time.
*We use bar graphs for comparing noncontinuous, categorical information.
E. Histogram

A ____________________________ is a special type of bar graph that is used to represent a
continuous set of data that is broken down into intervals (or ranges).
o

Here is an example of a histogram:
Let’s compare a histogram with a regular bar graph:

The differences between a histogram and a regular bar graph:
1) The bars in a histogram are touching while the bars in a regular bar graph are not
touching.
2) A histogram has data that is broken up into intervals or ranges, while a regular bar
graph has data that is broken down into categories.
3) A histogram displays continuous data, while a regular bar graph displays noncontinuous
data.
*We use histograms to display a continuous set of data that is broken down into intervals (or
ranges).
F. Line Graph

A ________________ ___________________ is a type of graph that displays information as a
series of data points connected by straight line segments. Every line graph has an x-axis and a yaxis.
o Here are three examples of line graphs:
Value of Sarah's Car
Temperatures In NY
City
Year
Value
2001
$24,000
2002
$22,500
2003
$19,700
2004
$17,500
2005
$14,500
2006
$10,000
Line
2007
$ 5,800
*We
Day
Temperature
1
43° F
2
53° F
3
50° F
4
57° F
5
59° F
Temperature of Heated Water
Heating Time
Water
(minutes)
Temperature
(°C)
0
50
1
60
2
70
3
80
4
90
5
100
graphs can also be straight lines.
6
67° F
use a line graph for continuous data
because it shows patterns, trends,
and relationships more clearly. In other words, line graphs are used to display the change in a
set of data over time.
II. REVIEW: When should you use which graph?
A. Circle Graph:
 displaying _________________________ or __________________ of a whole
B. Box-and-Whisker Plot:
 _______________________ a large set of data into _______ equal parts (quartiles) so that it’s
easier to understand

___________________ two sets of data (especially when they have the same mean or average)
C. Stem-and-Leaf Plot:

_________________________ a large set of data so that it’s easier to understand
D. Bar Graphs:

displaying _________________, _____________________ data such as shoes, pets, and
populations
E. Histograms:

displaying a _________________________set of data that is broken down into
__________________ (or ranges)

displaying _________________________ or how often an individual data item occurs or shows
up
F. Line Graphs:

displaying _______________________ over _______________________ (or progress)
III. REVIEW: The Difference Between A Histogram and A Regular Bar Graph

There are 3 differences between a histogram and a regular bar graph:
1) The bars in a histogram are __________________________, while the bars in a regular
bar graph are not _____________________________.
2) A histogram has data that is broken down into ______________________________ (or
ranges), while a regular bar graph has data that is broken down into
________________________.
3) A histogram displays _____________________________ data, while a regular bar graph
displays ________________________________ data.
IV. Choosing the Appropriate Representation
1) The amount of money Connor earns while working is shown below.
Work Earnings
Time Worked
(hours)
1
2
3
4
5
Income
(dollars)
10
20
30
40
50
Which type of display would BEST show the relationship between the time worked and the income
earned?
A) circle graph
B) bar graph
C) line graph
D) box-and-whisker plot
2) Ashley surveyed all the students in Mr. Chen’s class about their favorite ice cream flavor. She wants to
display the various responses as percents of the total number of response she received. Which would be
the BEST way for the committee to display these costs?
A) pie graph
B) histogram
C) stem-and-leaf plot D) box-and-whisker plot
3) Sheyenne recorded the high and low temperatures in Wahiawa for each day during one month. Which
type of display should she use to compare the differences between the high and low temperatures for each
day?
A) pie chart
B) bar graph
C) stem-and-leaf plot
D) box-and-whisker plot
4) Brittany scored 78, 45, 68, 88, 91, 94, 98, and 95 on her last eight tests in Mr. Chen’s class. Which
would BEST display Brittany’s progress in Mr. Chen’s class?
A) Venn diagram
B) line graph
C) stem-and-leaf plot
D) box-and-whisker plot
5) Terry kept a record of the various colors Mr. Chen’s students worn last Tuesday.
Colors Worn by Mr. Chen’s Students
Color
Number of
Students
12
14
5
6
11
18
2
Red
White
Orange
Green
Purple
Blue
Brown
Which type of display would BEST show the color worn by the greatest percentage of students last
Tuesday?
A) bar graph
B) circle graph
C) stem-and-leaf plot
D) box-and-whisker plot
6) At recess, students at Pioneer Middle School have a choice of participating in the following sports:
soccer, basketball, table tennis, volleyball, and football. Which graphical representation would BEST
display the number of students that participate in each sport at recess?
A) box-and-whisker plot
B) stem-and-leaf plot
C) bar graph
D) line graph
7) One hundred students were surveyed about what genre of music they prefer. The results are shown on
the table below.
Music Survey Results
Genre of
Music
Europop
Hip Hop
Country
Rock
Techno
Number of
Students
38
12
4
16
30
Which type of visual display would be BEST for this data?
A) pie chart
B) line plot
C) box-and-whisker plot
D) stem-and-leaf plot
8) Dylan conducted a survey of the students in Wheeler Middle School to determine what new elective
should be added to the course options. Which graphical representation would be MOST appropriate for
Dylan to show the percentage of students who voted for each elective?
A) line plot
B) histogram
C) box-and-whisker plot
D) circle graph
9) An auto mechanic charges a service fee of $50 plus $60 per hour. Which graphical representation
should be used to show the relationship between t, the total cost of a repair, and h, the number of hours
worked on the repair?
A) stem-and-leaf plot
B) pie chart
C) line graph
D) Venn diagram
10) In 2004, the population of the United States was approximately 300,000,000. The table below shows
the population broken down into the age groups of 0-18 and older than 18.
Population of the United States
Age
0-18
Older than 18
A) box-and-whisker plot
B) Venn diagram
C) circle graph
D) line graph
Population
105,000,000
195,000,000
11) Mrs. Watkins surveyed students in his school to find the total number of hours they spend on
homework each week. She wants to use a graph to show that the largest percentage of students spent 6 to
8 hours on homework each week.
Which type of graph would be most appropriate for Mrs. Watkins to use?
A) Circle graph
B) Histogram
C) Line graph
D) Box-and-whisker plot
12) The number of cars rented from a local rental0car company each day during the first eight days in a
month is shown below.
15, 20, 27, 40, 35, 10, 12, 13
Which graphic display would be BEST for finding the median number of cars rented?
A) tally chart
B) box-and-whisker plot
C) bar graph
13) The table below shows the results of a test given by Mr. Carlson.
Which is MOST appropriate to represent the data in the table?
D) venn diagram
Test Results in Mr. Carlson’s Class
Score
100
90
80
70
60
50
40
A) bar graph
C) venn diagram
Number of Students
2
10
7
4
2
3
1
B) line graph
D) scatter plot
14) Seymour Boogieman’s pre-algebra scores for his 10 tests are listed below.
Which graphic display would be BEST for Seymour to use to represent his mediant test?
A) tally chart
B) line graph
C) circle graph
D) stem-and-leaf plot
15) Schoen wants to conduct a report that shows the number of years each teacher has worked at the
school. He wants to group the data into 3-year intervals. Which data display should he use?
A) double bar graph
B) venn diagram
C) line graph
D) histogram
16) Daniel has a table listing the states with the largest populations in the years 1990 and 2005 as shown
below.
Daniel’s Table
States with the Largest Populations in the Years 1990 and 2005
State
Total Population in 1990
Total Population in 2005
Illinois
2,783,726
2,842,518
Texas
1,630,553
2,016,582
Pennsylvania
1,585,577
1,463,281
Which type of display is MOST appropriate for the data in the table?
A) double bar graph
B) circle graph
C) histogram
D) box-and-whisker plot