• A study conducted at ANU finds that a typical office worker spends an average of 13 minutes per hour on non work related activities such as face book. On a trial basis, management sets up a new enclosed work station for a randomly selected group of 12 workers and finds that the average number of minutes lost per hour is 11.3 with a standard deviation of 3.7. At the 5% level of significance, can we conclude that the work station represents a significant change?