Smart Charts - Pie Charts

A Pie Chart, also known as a circle graph, is a way of showing data using a circle divided into 'slices'. The entire circle represents the whole amount or the total frequency of the data collected.

The size of each slice represents its share of the total. Visually, a larger slice indicates a higher value, while a smaller slice indicates a lower value. If you see a slice that looks like a perfect 'L' shape starting from the center, it usually represents a quarter or $\frac{1}{4}$ of the total.

In a Pie Chart, a straight line passing through the center (the diameter) divides the circle into two equal parts. Each part represents exactly half or $\frac{1}{2}$ of the total data.

If a circle is divided by two perpendicular lines (lines crossing at a $90^{\circ}$ angle) through the center, it creates four equal sections. Each of these sections is called a 'quarter' and represents $\frac{1}{4}$ of the whole.

We can find the exact number for any slice by multiplying the fraction it represents by the total number. For example, if a chart represents $20$ children and the 'Apples' slice is $\frac{1}{2}$ of the circle, the number of children who like apples is $10$.

The sum of all the slices in a Pie Chart always adds up to the whole. In terms of fractions, the sum of all parts is equal to $1$. Visually, there are no gaps or overlaps between the slices.

Pie Charts are very useful for comparing parts of a group to the whole group at a single glance, such as comparing the number of students who walk to school versus those who take the bus.