A Pie chart is a circular diagram divided into sectors, with the size of each sector representing the magnitude of data it is depicting. Each sector of a pie chart can either be displayed in percentages (note all sectors must add up to 100%) or as an angle (note all sectors must add up to 360^{o}).

Example

The table below lists some of the most popular football clubs and the number of students at a given institution that supports each. Use a Pie chart to represent the information given in the table.

Football Clubs |
Number of Students |

Chelsea | 50 |

Manchester United | 200 |

Barcelona | 350 |

Real Madrid | 150 |

Inter Milan | 25 |

Arsenal | 100 |

Liverpool | 40 |

AC Milan | 75 |

The Pie Chart above depicts each sector as percentages. To calculate the percentages for each sector use the formula below:

% of a sector = Number of students x 100

Total number of students

So, to calculate the percentage of Chelsea fans:

% of Chelsea fans = 50 x 100

990

% of Chelsea fans = 5%

For Pie charts which depicts each sector as angles, the angles for each sector is found using the formula below:

Angle of a sector = Number of students x 360

Total number of students

So, to calculate the angle of the Chelsea sector:

Angle of Chelsea sector = 50 x 360

990

Angle of Chelsea sector = 18^{o}

**Note**: In most cases the questions set on Pie charts require those drawn depicting sectors in percentages.