Question

What is the standard error of the proportion if 80% of the 1,200 respondents in a yes/no survey answered "no"?
3.46%
2.31%
1.15%
2.58%
1.29%

Answer 1

The standard error of the sample proportion is given by:
\[\large \sqrt{\frac{p(1-p)}{n}}\]
where p is the sample proportion as a decimal and n is the sample size.