Question

The compressive strength of concrete is normally distributed with mu = 2500 psi and sigma = 50 psi. A random sample of n = 8 specimens is collected. What is the standard error of the sample mean?
Round your final answer to three decimal places (e.g. 12.345).

The standard error of the sample mean is __ psi.

Answer 1

Answer:

The standard error of the sample mean is _17.677_ psi.

Step-by-step explanation:

Explanation:-

A random sample of n = 8 specimens is collected.

Given sample size is n = 8

Given mean of the population 'μ' = 2500 psi

standard deviation 'σ' = 50 psi

Let x⁻ is the mean of the observed sample

Standard error of the sample mean = $\frac{S.D}{\sqrt{n} }$      ...(i)

Given Population of standard error (S.D) 'σ' = 50 psi

Now substitute all values in (i)

$S.E = \frac{50}{\sqrt{8} } =17.677$

Conclusion:-

The standard error of the sample mean is _17.677psi.