Respuesta :
Answer:
The standard deviation of the sampling distribution of sample means for whenever service life is in control 10 hours.
Step-by-step explanation:
The standard error ([tex]\sigma_{M}[/tex]) of the mean is the standard deviation of the sampling distribution of the mean.
The formula to compute the standard error is:
[tex]\sigma_{M}=\frac{\sigma}{\sqrt{n}}[/tex]
The information provided is:
[tex]\sigma = 20\ \text{hours}\\n=4[/tex]
Compute the standard deviation of the sampling distribution of sample means for whenever service life is in control as follows:
[tex]\sigma_{M}=\frac{\sigma}{\sqrt{n}}[/tex]
[tex]=\frac{20}{\sqrt{4}}\\\\=\frac{20}{2}\\\\=10\ \text{hours}[/tex]
Thus, the standard deviation of the sampling distribution of sample means for whenever service life is in control 10 hours.
