Final answer:
A pie graph, also known as a pie chart, is used to show how an overall total is divided into parts. It represents a group as a whole with a circle, and the slices of the pie show the relative sizes of the subgroups.
Step-by-step explanation:
A pie graph, also known as a pie chart, is used to show how an overall total is divided into parts. It represents a group as a whole with a circle, and the slices of the pie show the relative sizes of the subgroups. This type of chart is commonly used when illustrating the relationship of the parts to the whole.