Two-sided Confidence Intervals

The two-sided $100\cdot(1-\alpha)\%$ confidence interval is centered at $\hat{p}$ and has upper and lower limits given by:

   upper limit$$\;=\;\hat{p}+z_{\alpha/2}\cdot\sqrt{\frac{\hat{p}(1-\hat{p})}{n}}$$   Cell B17

   lower limit$$\;=\;\hat{p}-z_{\alpha/2}\cdot\sqrt{\frac{\hat{p}(1-\hat{p})}{n}}$$   Cell B19