#### description

- Histogram

#### notes

Let us again consider the grouped frequency distribution of the marks obtained by 60 students in Mathematics test.

Class interval |
Frequency |

0 - 10 | 2 |

10 - 20 | 10 |

20 - 30 | 21 |

30 - 40 | 19 |

40 - 50 | 7 |

50 - 60 | 1 |

Total | 60 |

This is displayed graphically as in the adjoining graph in following fig.

Observe that, here we have represented the groups of observations (i.e., class intervals) on the horizontal axis. The height of the bars show the frequency of the class-interval. Also, there is no gap between the bars as there is no gap between the class-intervals.

The graphical representation of data in this manner is called a histogram.

The following graph is another histogram in fig .