In some series the lower class limit of the first class interval and the upper limit of the last class interval are missing, “less than” or below is specified in place of he lower class limit of the first class interval and “more than” or below is specified in place of the lower class limit of the first class interval and ‘more than’ or above is specified in place of the upper class limit of the last class interval.
Example:
| Marks |
Frequencies |
| Below 5 |
2 |
| 5 - 10 |
6 |
| 10 - 15 |
8 |
| 15 and above |
12 |
