Samples of size n = 9 are selected from a population with μ = 80 with σ = 18. what is the expected value of m, the mean of the distribution of sample means?

80

Explanation:

The mean of the distribution of sample means always target the population mean. What this line tells is that whatever the population mean will be, the mean of the distribution of sample means will be same. Since the population mean is 80, the mean of distribution of sample means will also be 80.

However, the standard deviation of the sample distributions is different and is equal to the population standard deviation divided by square root of sample size. So in this case the standard deviation of distribution of sample means will be 6.