Key learning points

1. Knowing the angle size for a sector allows calculation of the frequency.
2. By knowing the total, statements can be made comparing the data.
3. Different pie charts may have different totals even though proportions are the same.

Common misconception

Keywords

• Pie chart - A pie chart (pie graph) is a circular graph where sectors represent different groups proportionally.

• Frequency - The frequency is the number of times an event occurs; or the number of individuals (people, animals etc.) with some specific property.

• Sector - A sector is the region formed between two radii and their connecting arc.

• Proportion - Proportion is a part to whole (sometimes part to part) comparison. If two things are proportional, the ratio of part to whole is maintained

• Degrees - Degrees are the most common unit of measurement for angle. One whole turn is equal to 360 degrees, written 360°.