Solution
Part a
p=x/n = 519/1003= 0.517
Part b
The margin of error is given by:
[tex]ME=z_{\frac{\alpha}{2}}\cdot\sqrt[]{\frac{p(1-p)}{n}}[/tex]At 99 % confidence level the z value is z= 2.576
Replacing we got:
[tex]ME=2.576\cdot\sqrt[]{\frac{0.517(1-0.517)}{1003}}=0.0407[/tex]Rounded it would 0.041
Part c
For this case we can find the confidence interval on this way:
[tex]0.517\pm0.041=(0.476;0.558)[/tex]Part d
For this case the correct answer is:
c. One has 99% confidence that the interval from the lower bound to the upper bound actually does contain the true value of the population proportion