The number of years of education of self-employed individuals in the United States has a population mean of 13.6 years and a population standard deviation of 3.0 years. If we survey a random sample of 100 self-employed people to determine the average number of years of education for the sample, what is the mean of the sampling distribution of x-bar (the sample mean)?

Answer 1

SEm = SD/√n = 3/√100 = 3/10 = .3

sample mean = 13.6 ± .3 (68% of the time)