It is appropriate to compute a confidence interval for a population proportion p if $n \hat { p }$
and $n ( 1 - \hat { p } )$
are both at least 5.

Question

It is appropriate to compute a confidence interval for a population proportion p if $n \hat { p }$ 
and $n ( 1 - \hat { p } )$ 
are both at least 5.

Quizplus · Accepted Answer

This rule ensures that the sample size is large enough for the normal approximation to the binomial distribution to be appropriate, which is a key assumption for computing confidence intervals for population proportions.

It Is Appropriate to Compute a Confidence Interval for a Population