Answer:
The 95% confidence interval for the population proportion is (0.778, 0.884).
Step-by-step explanation:
We have to calculate a 95% confidence interval for the proportion.
The sample proportion is p=0.831.
The standard error of the proportion is:
[tex]\sigma_p=\sqrt{\dfrac{p(1-p)}{n}}=\sqrt{\dfrac{0.831*0.169}{195}}\\\\\\ \sigma_p=\sqrt{0.00072}=0.027[/tex]
The critical z-value for a 95% confidence interval is z=1.96.
The margin of error (MOE) can be calculated as:
[tex]MOE=z\cdot \sigma_p=1.96 \cdot 0.027=0.053[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=p-z \cdot \sisgma_p = 0.831-0.053=0.778\\\\UL=p+z \cdot \sisgma_p = 0.831+0.053=0.884[/tex]
The 95% confidence interval for the population proportion is (0.778, 0.884).
