Lesson on Comparing Graphs [Excerpt from The Math
Goodies CD]
In this unit, we learned about line, bar and circle graphs. We learned how to
read and interpret information from each type of graph, and how to construct
these graphs. If you were asked to create a graph from a given set of data, how would
you know which type of graph to use? Which graph we choose depends on the type
of data given and what we are asked to convey to the reader. The information
below will help you determine which type of graph to use.
| Tables are used to organize exact amounts of data and to display
numerical information. Tables do not show visual comparisons. As a result,
tables take longer to read and understand. It is more difficult
to examine overall trends and make comparisons with tables than it is with graphs. |
 |
| Line graphs are used to display data or information that changes
continuously over time. Line graphs allow us to see overall trends such as
an increase or a decrease in data over time. |
|
| Bar graphs are used to compare facts. The bars
provide a visual display for comparing quantities in different categories
or groups.
Bar graphs help us to see relationships quickly. Bar graphs can be
difficult to read accurately. A change in the scale in a bar graph may alter one's visual
perception of the data. |
|
| Circle Graphs are used to compare the parts of a whole. Circle
graphs represent data visually in the same proportion as the numerical
data in a table: The area of each sector in a circle graph is in the same
proportion to the whole circle as each item is to the total value in the
table. Constructing an accurate circle graph is difficult to do without a
computer. This is because you must first find each part of the whole
through several elaborate calculations and then use a protractor to draw
each angle. This leaves a lot of room for human error. Circle graphs are
best used for displaying data when there are no more than 5 or 6 sectors
and when the values of each sector are different. Otherwise they can be
difficult to read and understand. |
Unit 11: Data and Graphs (from the Math Goodies CD)
 |
Data and Line Graphs |
 |
Constructing Line
Graphs |
 |
Data and Bar Graphs |
 |
Constructing Bar Graphs |
 |
Data and Circle Graphs |
 |
Constructing Circle Graphs |
 |
Comparing Graphs |
 |
Practice Exercises |
 |
Challenge Exercises |
 |
Solutions |
|
Top of Page | Worksheet
Menu | Puzzle Menu | Game Menu
| Main Menu
|
Copyright © 2007-2010 Gisele Glosser. All Rights Reserved.
|