You will circle graphs for representing and displaying data.
After completing this tutorial, you will be able to complete the following:
Constructing circle graphs
Circle graphs can provide a quick and easy way to display information about the relationship of parts to a whole. Once the categories are selected and data collected for each category, a circle graph can be constructed.
Let's look at an example of the number of running shoes sold in a given month:
By looking at the table, we can see that Stone and Fast have the largest sectors of shoe sales, but constructing a circle graph would help us to view this quickly. To create a circle graph, we need to determine the following:
· What is the "whole?"
· What are the different parts or groups?
· What is the ratio of each part to the whole?
· What is the degree of each section?
Defining the whole
In this table, the whole is the total number of running shoes sold for the month. This total can be found by adding up the numbers sold for each type of shoe. There are five different parts to the whole and the table lists the number sold in each part.
150 + 108 + 192 + 60 + 90 = 600 total shoes sold
Determining the parts or groups
There are five parts to the whole. Each data group is a category of running shoe brands:
1) Fast, 2) Easy Walk, 3) Stone, 4) RNR, and 5) Other.
Finding the ratio of each part to the whole
Now that we know how many parts there are and the total, we can create ratios of each part to the whole.
Calculating the degree of each section
Using the ratios of each part, we are able to calculate the degree of each category. A full circle is made up of 360°. So in order to find the degrees of each part, we must multiply the ratio of each part by 360.
Now that we have calculated the degree for each category, we can use those measurements to draw the circle graph.
This graph allows us to evaluate the relative sizes of each category quickly. We can see that Stone has the highest number of sales and that of the top four sellers, RNR has the lowest?approximately one-third that of Stone.
|Approximate Time||20 Minutes|
|Pre-requisite Concepts||Students should know the definition of ratio, and be able to perform mathematical operations on whole numbers.|
|Type of Tutorial||Concept Development|
|Key Vocabulary||circle graph, display data,|