Use the data in Example 1 to construct a 95% confidence interval for the mean number of hours spent on required athletic activities by all student-athletes in the conference.

Data from Example 1

A researcher is collecting data about a college athletic conference and its student-athletes. A random sample of 40 student-athletes is selected and their numbers of hours spent on required athletic activities for one week are recorded (see table at left). Find a point estimate for the population mean μ, the mean number of hours spent on required athletic activities by all student-athletes in the conference.

19 25 Number of hours 25 15 21 22 20 20 22 22 21 21 23 22 16 21 18 25 23 23 21 22 24 18 19 23 20 19 19 19 19 24 25 17 21 21 25 23 18 22 20 21 22 20 21 21