Mathematics
A class teacher has the following absentee record of 40 students of a class for the whole term. Find the mean number of days a student was absent.
| No. of days | No. of students |
|---|---|
| 0 - 6 | 11 |
| 6 - 10 | 10 |
| 10 - 14 | 7 |
| 14 - 20 | 4 |
| 20 - 28 | 4 |
| 28 - 38 | 3 |
| 38 - 40 | 1 |
Measures of Central Tendency
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Answer
We construct the following table :
| No. of days (Classes) | Class mark (yi) | No. of students (Frequency (fi)) | fiyi |
|---|---|---|---|
| 0 - 6 | 3 | 11 | 33 |
| 6 - 10 | 8 | 10 | 80 |
| 10 - 14 | 12 | 7 | 84 |
| 14 - 20 | 17 | 4 | 68 |
| 20 - 28 | 24 | 4 | 96 |
| 28 - 38 | 33 | 3 | 99 |
| 38 - 40 | 39 | 1 | 39 |
| Total | 40 | 499 |
∴ Mean = = 12.475
Hence, mean of the following distribution is 12.475
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