Answer: 756
Step-by-step explanation:
Given : The proportion of adults over 50 never graduated from high school. = 0.23
Margin of error : E=0.03
Significance level : [tex]\alpha=1-0.95=0.05[/tex]
Critical value : [tex]z_{\alpha/2}=1.96[/tex]
The formula to find the sample size is given by:_
[tex]n=p(1-p)(\dfrac{z_{\alpha/2}\ }{E})^2[/tex]
i.e. [tex]n=(0.23)(0.77)(\dfrac{(1.96)}{0.03})^2=755.941511111approx756[/tex]
Hence, the required minimum sample size = 756
