"Education is the most powerful tool we can use to change the world."-Nelson Mandela
Graphs are an essential part to learning mathematics. Graphs show data and allow people to understand that data. Their are many different types of graphs that will be taught in this chapter; circle graphs, bar graphs, line graphs, and scatter plot graphs. The goal of this chapter is to teach each one of these graphs and for students to understand how to read these graphs. They will also be able to know how to create each graph based on data they are given. They will learn each step in order to make each graph.
The objective of each section is to show these graphs and teach about the current history and past history at Saint Joseph's University. Another objective is for the students to be able to read, understand, and create their own circle, bar, line, and scatter plot graphs.
Saint Joseph's University, Barbellin Hall/Sweeney Field
Section 1: Circle Graphs
This circle graph is showing the Business Majors at Saint Joseph's University. Along with each major this university provides, it is also showing how many other areas you can go into under that major. Business is a very popular major at this university and as you can see from this graph, there are many different business majors and minors that students can go into for their academics.
This circle graph shows certain data that was collected. Once the data was collected, the graph was then made. Circle graphs are used to show the results of data in a proportional manner. You can see the percentages of each result and how it compares to other results.
Vocabulary to know:
Circle Graph- A circle chart divided into sections which represent a value out of the overall value.
Percentage- Any proportion or share in relation to a whole.
Data- Facts and statistics collected together for reference or analysis.
Average- Obtaining the result by adding all of the quantities together and then dividing by how many quantities there are.
Degree- A unit of measurement of angles.
This video is a good quick lesson on how to make circle graphs. You can watch this for more help! The following are detailed steps in order to make this circle graph.
To read a circle graph, you look at each category and see what percentage of the circle it has. This is out of 360%, because a circle is 360 degrees. You can see how much each category is by comparing them to each other category.
Step 1: Collect data and have the data separated into categories that can be split up.
Step2: Once the data is split up, take each category and their values (numbers) and order them from the largest to the least. You will need to take the average of them all to see how much each category will take up of the graph. For example, the circle graph shown of the business majors would be each number of majors and their minors, which is 17. After you have the total of the whole circle graph, you will use that number, 17 in this case, and divide each major by 17 to get the average of each major. For Marketing, you will do 4 (value of marketing) divided by 17 (total values for the graph). This equals 0.23529. After doing this for each category/major, you will now get a percentage for each major. You will take each percentage and multiply each by 360 degrees because a circle is 360 degrees. For Marketing, you take the 0.23529 and multiply that by 360, which equals 84.7%. That is how much of the graph, out of 360%, is marketing. Once you have each percentage, you will take a protractor and measure each degree that you have gotten for each value.
Step 3: You make each part of the circle graph and label each part with what it represents. Make sure to have a title for the graph as well. You can color code the chart so it is easier to read and see each different type of data.
This is another video explaining pie charts.
1.) What do you need to divide each value by in order to get a percentage of the circle graph?
2.) Make a circle graph with the following data of students favorite ice cream flavors: Chocolate-6, Vanilla-10, Mint Chocolate Chip-12, Rocky Road-4, Cookies and Cream-5
Section 2: Bar Graphs
Many objects can look like graphs too!
Bar graphs are used by many people to easily show the results of some type of experiment. Using bar graphs, it makes it easier to see the comparison between different results.
Vocabulary to know:
Bar Graph- A graphical display of data using bars or different heights.
Y-Intercept- The axis that is vertical of a system of coordinates.
X-Intercept- The horizontal axis of a system of coordinates.
Interval- The consistent space in between numbers.
Below is an example of a bar graph that you can look at. You can use this website to make your own graphs.
This bar graph shows the Men's Varsity sports teams at Saint Joseph's. As you can see, there are many teams and many students that play on each team. Sports are a great extra-curricular activity and a great way to make friends and stay in shape! Sports are a big part of this university and are important to many students.
Bar graphs are used for data that need to be compared. The data is separated into categories and you can compare each category separately.
In order to read a bar graph you look at the x-axis and that is your category you are trying to find the value of. You look to see where the bar goes until and look at the y-axis to see what value it is at. This is your data that was graphed.
Each category has a certain value and that value is what is being shown by the bar graph. To start making a bar graph, you need the data and to separate them into categories. Once you have your categories, see how many is in each and that is the value. Once you have the values for each category, you will begin to make the bar graph.
Start with drawing your x-axis (horizontal) and y-axis (vertical) and label them with what you are graphing. Shown below.
Next, look at your values and try and figure out what interval you will go by on your graph. This will be on your y-axis, numbers going from 0 to your highest value. Once you have your interval, start labeling the graph with the values on the y-axis.
Now, label your x-axis with your category name or with what you are graphing. You may need to find an interval for this axis as well.
After your graph is completely labeled, you can now start to draw the bars of data. Start from the left and see what your data is showing you, and draw a bar where the value is (y-axis). Continue this for each category and make sure all of your data is showing on the graph.
1.) Explain the difference between the x-axis and y-axis.
2.) What are bar graphs used for?
Section 3: Line Graphs