Question

The standard deviation of a population is known to be 7.8. If the sample size is 85, what is the standard error of the mean?
A. 0.22

B.0.85

C.1.047

D.6.008

Answer 1

The standard error of the sample mean is really just the standard deviation of the sample mean.
\[\large Standard\ error=\frac{\sigma}{\sqrt{n}}\]
where sigma is the population standard deviation and n is the sample size.