1. A previous survey showed that 83% of the people who take the daily newspaper read the sports section. What sample size is needed to be 90% confident that the true
proportion is within 3%?
2. Find the 90% confidence interval for the population standard deviation if a sample of 16 had a standard deviation of 2.4.
3. Find the 99% confidence interval for the population standard deviation if a sample of 27 had a standard deviation of 25.4.
4. In a sample of 250 dogs, 30 were registered with the AKC. What is the 95% confidence interval for the population proportion?
5. What sample size is needed to find the percent of the customers at a store that are married, if 90% confidence is desired to be within a 5% margin of error?