Question

We draw a random sample of size 36 from a population with the standard deviation 3.5. if the sample mean is 27, what is a 95% confidence interval for the population mean?

Answer 1

95% refers to 2 standard errors from sample mean (SE)


`SE = (s)/(√(n)) = (3.5)/(√(36)) = (3.5)/(6) = 0.583`

Confidence interval is:

`[27 -2(.583), 27+2(.583)]`