| Testing Mean with known Variance | |
| sample size | 63 |
| population variance | 13.78 |
| sample mean | 21.15 |
| null hypothesis about mean | 20 |
| type I error | 0.05 |
| critical value (one-tailed) | 20.7692749503043 |
| confidence interval (two-tailed) (sample mean) | [ 20.2333523590791 , 22.0666476409209 ] |
| conclusion for one-tailed test | |
| Reject the null hypothesis. | |
| conclusion for two-tailed test | |
| Reject the null hypothesis | |