The Glen Valley Steel Company manufac_ ::"'7f':!:' tures stee I bars. I f the production process is working properly, it turns oUi steel bars that are normally distributed with mean length of at least 2.8 feet. Longer steel bars can be used or altered. bu

The Glen Valley Steel Company manufac_

::"'7f':!:' tures stee I bars. I f the production process is

working properly, it turns oUi steel bars that are normally

distributed with mean length of at least 2.8 feet. Longer

steel bars can be used or altered. but shorter bars must

be scrapped. You select a sample of 25 bars; the mean

length is 2.73 feet, and the sample standard deviation is

0.20 foot.

a. If you test the null hypothesis at the 0.05 level of significance,

what decision do you make using the critical value

approach to hypothesis testing?

b. If you test the null hypothesis at the 0.05 level of significance,

what decision do you make using the p-value

approach to hypothesis testing?

c. Interpret the meaning of the p-value in this problem.

d. Compare your conclusions in (a) and (b)