Answer:
5%
Step-by-step explanation:
This is a significance test for a mean.
The 2 hypothesis here will be:
[tex]H_{0}: \mu = 2,200 \\H_{a}: \mu > 2,200[/tex]
To determine the z-score of the error in the means you have to use this formula:
[tex]z= \frac{x-\mu}{\frac{\sigma}{\sqrt{n}} }[/tex]
[tex]z=\frac{2350-2200}{\frac{500}{\sqrt{40} } } =1.897[/tex]
This mean that if the z score of a significance level is less than 1.897 the hypothesis that μ>2,200 is suggested.
10% -> z= 1.28
5% -> z = 1.645
1% -> z = 2.33
The most restrictive level of significance is 5%
