A machine produces pipes used in airplanes. The average length of the pipe is 16 inches....

A machine produces pipes used in airplanes. The average length of the pipe is 16 inches. The acceptable variance for the length is 0.3 inches. A sample of 17 pipes was taken. The average length in the sample was 15.95 inches with a variance of 0.4 inches.

a.	Construct a 95% confidence interval for the population variance.
b.	State the null and alternative hypotheses to be tested.
c.	Compute the test statistic.
d.	The null hypothesis is to be tested at the 5% level of significance. State the decision rule for the test using the critical value approach.
e.	What do you conclude about the population variance?

Expert Solution

milcah answered 2 years ago

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