Question

In a study of cell phone use and brain hemispheric​ dominance, an Internet survey was​ e-mailed to 2473 subjects randomly selected from an online group involved with ears. 1181 surveys were returned. Construct a 90​% confidence interval for the proportion of returned surveys.

Answer 1

The total number of subjects to whom the internet survey was e-mailed is 2315

There were 931 surveys returned.

CI=(ˆp−E,ˆp+E)=(0.402−0.026,0.402+0.026)=(0.376,0.428)