Question

A random sample of n =300 observations from a binomial population produced x=125. Estimate the population proportion and determine the standard error.

Answer 1

$p=\frac{x}{n}=\frac{125}{300}=0.4167.$

$SE=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.4167(1-0.4167)}{300}}=0.0285.$