28. if random samples each with n=4 scores, are selected from a normal population with μ=80 and σ=10, then the distribution of sample means will have an expected value

u=80

The expected value of mean always equals the population mean.

Explanation:

Given a normally distributed population, when a number of random samples are selected from the Normal population, the expected value of the mean of the distribution of sample means always equals the population mean. Sample means can also be used to draw inference on the entire population mean.

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