The 2010 General Social Survey asked the question: “For how many days during the past 30 days was your mental health not good? ” Based on responses from 1,151 US residents, the survey reported a 95%...

The 2010 General Social Survey asked the question: “For how many days during the past 30 days was your mental health not good? ” Based on responses from 1,151 US residents, the survey reported a 95% confidence interval (3.40,4.24) days in 2010.

(a) Determine the sample mean and the sample standard deviation of the sample.

(b) Using the data found in (a), construct a 90% confidence interval for the mean µ of the population. Compare the two intervals.