## Elementary Statistics (12th Edition)

a) The best point estimate is equal to the proportion of the sample (x) divided by the sample size: $\hat{p}=\frac{x}{n}=\frac{531}{1002}=0.53.$ b)$E=z_{\frac{\alpha}{2}}\cdot \sqrt{\frac{\hat{p}\cdot (1-\hat{p})}{n}}=1.96\cdot \sqrt{\frac{0.53\cdot (1-0.53)}{1002}}=0.0309.$ c) Confidence interval: $\hat{p}-E$