The confidence interval estimator of the population proportion is given by
[tex]C.I.=\hat{p}\pm M.E.[/tex]
where: [tex]\hat{p}[/tex] is the sample proportion, which is midway between the two intervals and M.E. is the margin of error which is the difference between each of the intervals and the sample proportion.
i.e.
[tex]\hat{p}= \frac{76+84}{2} \% \\ \\ = \frac{160}{2} \%=80\%[/tex]
Therefore, the margin of error is 4%.
