## Frequency Polygons

Frequency polygons show the same information as bar charts, with points joined by lines instead of with vertical bars. Suppose we need to draw a frequency polygon for the data in the table below which contains information about the weights of some ambitious slimmers.

Weight,in kg | Frequency |

12 | |

35 | |

76 | |

80 | |

41 | |

17 |

The frequency polygon is:

Notice that the points are plotted as (midpoint of weight interval, frequency).