It seems these days that college graduates who are employed full-time work more than 40-hour weeks. Data are available that can help us decide if this is true. A survey was recently sent to a group of adults selected at random. There were 21 respondents who were college graduates employed full-time. The mean number of hours worked per week by these 21 respondents was 44 hours, with a standard deviation of 9 hours.

Assume that the population of hours worked per week by college graduates employed full-time is normally distributed with mean . Can we conclude that is greater than 40 hours? Use the .01 level of significance.

Perform a one-tailed test. Then fill in the table below.

1. Null hypothesis

2. Alternative hypothesis

3. What kind of test statistic t z chi f

4. Test statistic (3 decimal places)

5. P value (3 decimal places)

6. Can we conclude that the mean number of hours is greater than 40