Question

What is the approximate width of a 90 percent confidence interval for the true population proportion if there are 12 successes in a sample of 25? ± .480 ± .164 ± .206 ± .196?

Answer 1

`\hat{p}=(12)/(25)=0.48`
An approximate 90% confidence interval for the true population proportion p is given by:

`\hat{p}\pm 1.645 \sqrt{(0.48(1-0.48))/(25)} =\hat{p}\pm0.164`
The correct choice of answer is the second one (b).