| A | B |
Sample size | 200 | 198 |
Get to the bottom of the grades | 16.58 ± 6.42 | 17.71 ± 6.80 |
Measured results | 22.13 ± 5.80 | 17.23 ± 7.11 |
T | 19.866 | −1.174 |
P | <0.05 | 0.242 |