The Humans Relations Director at Ford began a study of the overtime hours in the Inspection Department. A sample of 15 workers showed they worked the following number of overtime hours last month:
13 13 12 15 7 15 5 12
6 7 12 10 9 13 12
I need to compute the arithmetic mean and indicate whether it is a statistic or parameter.
I really don't understand this at all. If I could get some help, I'd really appreciate it.