# 8.3.1. Collecting and Organizing Data

The following are the grades of 30 students in a monthly math exam:

25 | 37 | 31 | 39 | 26 | 23 | 27 | 31 | 20 | 33 |

35 | 37 | 23 | 37 | 21 | 33 | 24 | 27 | 36 | 27 |

32 | 26 | 30 | 37 | 25 | 31 | 32 | 21 | 28 | 32 |

Complete the following frequency table with the correct frequencies.

Grades | 20– | 24– | 28– | 32– | 36– | Total |
---|---|---|---|---|---|---|

Frequency | 30 |

- A5, 8, 5, 6, 6
- B6, 8, 7, 4, 5
- C3, 7, 5, 8, 7
- D4, 7, 4, 3, 5

### Example

The following are the grades of 30 students in a monthly math exam:

25 | 37 | 31 | 39 | 26 | 23 | 27 | 31 | 20 | 33 |

35 | 37 | 23 | 37 | 21 | 33 | 24 | 27 | 36 | 27 |

32 | 26 | 30 | 37 | 25 | 31 | 32 | 21 | 28 | 32 |

Complete the following frequency table with the correct frequencies.

Grades | 20– | 24– | 28– | 32– | 36– | Total |
---|---|---|---|---|---|---|

Frequency | 30 |

### Solution

Count the number of grades for each set.

Using the previous data, the frequency table for the weekly wages can be completed as follows:

Grades | Total | |||||
---|---|---|---|---|---|---|

Frequency | 5 | 8 | 5 | 6 | 6 | 30 |