Question

A sample of 250 observations is selected from a normal population with a population standard deviation of 25. The sample mean is 20. Determine the standard error of the mean. (Round your answer to 3 decimal places.)

Answer 1

The standard error of the mean is
`\sigma _(\= x ) = 1.581`

Explanation:

From the question we are told that

The sample size is n = 250

The standard deviation is
`\sigma = 25`

The sample mean is
`\= x = 20`

The standard error of the mean is mathematically represented as

`\sigma _(\= x ) = (\sigma )/(√(n) )`

substituting values

`\sigma _(\= x ) = (25 )/(√(250) )`

`\sigma _(\= x ) = 1.581`