A local health centre noted that in a sample of 400 patients, 80 were referred to them by the local hospital. a. Provide a 95% confidence interval for all the patients who are referred to the health...

A local health centre noted that in a sample of 400 patients, 80 were referred to them by the local hospital.



a. Provide a 95% confidence interval for all the patients who are referred to the health centre by the hospital.

b. What sample size would be required to estimate the proportion of all hospital referrals to the health centre with a margin of error of 0.04 or less at 95% confidence?