Pie charts represent a whole amount and are shown in a circle graph. The size of each section of the chart, or slice of the “pie,” shows how large that thing is in comparison with the other sections and with the whole circle. Each section of the chart has a label telling you what that section represents, and may additionally show you the percent of the whole and the raw number.
For example, the pie chart to the right only has labels that tell you what each slice stands for, but no raw numbers or percents.
Often there will be percent value and less often the label will also display the raw number, as in the second example below which shows the number of dollars in addition to the percent of the overall budget each section takes up.
Let’s look at how you might be tested on your understanding of pie charts on the GED math test. You might be shown a pie chart like the one to the right and asked to use it to make a simple calculation. For example: The enrollment at the University of X is 35,400. How many African-American students attend the University of X. You can see from the chart that 31% of the students are African-American and since you know the total enrollment is 35,400 just multiply 35,400 by 0.31 and you’ll have the answer, which is 10,974 students.