Table 6.
Determination of Z-value according to the percentage of confidence level.
| Percentage | 80% | 85% | 90% | 95% | 99% | 99.5% | 99.9% |
|---|---|---|---|---|---|---|---|
| Z-value | 1.282 | 1.440 | 1.645 | 1.960 | 2.576 | 2.807 | 3.291 |
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