How do you calculate the margin of error when estimating a population mean instead of a proportion?

When estimating a population mean, the formula is: Margin of Error = z * (σ / √n), where 'z' is the z-score, 'σ' is the population standard deviation, and 'n' is the sample size. If the population standard deviation is unknown, you use the sample standard deviation (s) and a t-distribution instead of the z-distribution.