Pie charts
Pie charts can be drawn easily, if we remember the crucial fact that there are 360 degrees about the centre of the circle. We split this up to show the different quantities.
Example
An example would be the following results of where a group of pupils went for their summer holidays.
The results are given as percentages and need converting to degrees to be measured out and drawn.
The results are shown below:
| Destination | Percentage of pupils (%) | Calculation | Angle |
| Spain | 40 | \(\frac{{40}}{{100}} \times 360^\circ\) | \(144^\circ\) |
| America | 25 | \(\frac{{25}}{{100}} \times 360^\circ\) | \(90^\circ\) |
| France | 5 | \(\frac{{5}}{{100}} \times 360^\circ\) | \(18^\circ\) |
| Scotland | 20 | \(\frac{{20}}{{100}} \times 360^\circ\) | \(72^\circ\) |
| Greece | 10 | \(\frac{{10}}{{100}} \times 360^\circ\) | \(36^\circ\) |
| Destination | Spain |
|---|---|
| Percentage of pupils (%) | 40 |
| Calculation | \(\frac{{40}}{{100}} \times 360^\circ\) |
| Angle | \(144^\circ\) |
| Destination | America |
|---|---|
| Percentage of pupils (%) | 25 |
| Calculation | \(\frac{{25}}{{100}} \times 360^\circ\) |
| Angle | \(90^\circ\) |
| Destination | France |
|---|---|
| Percentage of pupils (%) | 5 |
| Calculation | \(\frac{{5}}{{100}} \times 360^\circ\) |
| Angle | \(18^\circ\) |
| Destination | Scotland |
|---|---|
| Percentage of pupils (%) | 20 |
| Calculation | \(\frac{{20}}{{100}} \times 360^\circ\) |
| Angle | \(72^\circ\) |
| Destination | Greece |
|---|---|
| Percentage of pupils (%) | 10 |
| Calculation | \(\frac{{10}}{{100}} \times 360^\circ\) |
| Angle | \(36^\circ\) |
Therefore, the pie chart looks like this:
