Adult Sleep Times (hours) of sleep for randomly selected adult subjects included in the National Health and Nutrition Examination Study are listed below. Here are the statistics

for this sample: n = 12, 5 = 6.8 hours, s = 2.0 hours. The times appear to be from a

normally distributed population. A common recommendation is that adults should sleep between 7 hours and 9 hours each night. Assuming that the mean sleep time is 7 hours, find the probability of getting a sample of 12 adults with a mean of 6.8 hours or less.

What does the result suggest about a claim that "the mean sleep time is less than 7 hours"?

4 8 4 4 8 6 9 7 7 10 7 8