Calculate Less than type Cumulative frequency table from the following grouped data
| Class | Frequency |
| 15 - 20 | 3 |
| 20 - 25 | 9 |
| 25 - 30 | 14 |
| 30 - 35 | 20 |
| 35 - 40 | 35 |
| 40 - 45 | 9 |
| 45 - 50 | 6 |
| 50 - 55 | 2 |
| 55 - 60 | 2 |
Solution:| Class | Frequency |
| 15 - 20 | 3 |
| 20 - 25 | 9 |
| 25 - 30 | 14 |
| 30 - 35 | 20 |
| 35 - 40 | 35 |
| 40 - 45 | 9 |
| 45 - 50 | 6 |
| 50 - 55 | 2 |
| 55 - 60 | 2 |
Less than cumulative frequency can be obtained by adding to the other frequencies.
| Class | Frequency | Less than type | Cumulative Frequency |
| 15 - 20 | 3 | Less than 20 | 3 |
| 20 - 25 | 9 | Less than 25 | 12 (= 3 + 9) |
| 25 - 30 | 14 | Less than 30 | 26 (= 12 + 14) |
| 30 - 35 | 20 | Less than 35 | 46 (= 26 + 20) |
| 35 - 40 | 35 | Less than 40 | 81 (= 46 + 35) |
| 40 - 45 | 9 | Less than 45 | 90 (= 81 + 9) |
| 45 - 50 | 6 | Less than 50 | 96 (= 90 + 6) |
| 50 - 55 | 2 | Less than 55 | 98 (= 96 + 2) |
| 55 - 60 | 2 | Less than 60 | 100 (= 98 + 2) |
This material is intended as a summary. Use your textbook for detail explanation.
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