Independent variable | N | Percent (%) | |
Gender | Boy | 150 | 50 |
| Girl | 150 | 50 |
| Total | 300 | 100 |
Age (years) | 8 | 100 | 33.3 |
| 9 | 100 | 33.3 |
| 10 | 100 | 33.3 |
| Total | 300 | 100 |