Question

 A population has mean and standard deviation of 20 and 3.15,

respectively. What is the standard error of the mean of the sampling

distribution in a sample size of 5? complete solution

Answer 1

The standard error of the mean is the standard deviation of the sample means. If the population standard deviation is $\sigma$ and the sample size is n, then the standard deviation of the sample means is:

$\sigma_{\bar{x}} = \frac{\sigma}{\sqrt{n}} \\ \sigma_{\bar{x}} = \frac{3.15}{\sqrt{5}} = 1.40$