An Automobile Dealer Wants to See If There Is a Relationship

question 57

Essay

An automobile dealer wants to see if there is a relationship between monthly sales and the interest rate. A random sample of 4 months was taken. The results of the sample are presented below. The estimated least squares regression equation is = 75.061 - 6.254X
a.Obtain a measure of how well the estimated regression line fits the data.
b.You want to test to see if there is a significant relationship between the interest rate and monthly sales at the 1% level of significance. State the null and alternative hypotheses.
c.At 99% confidence, test the hypotheses.
d.Construct a 99% confidence interval for the average monthly sales for all months with a 10% interest rate.
e.Construct a 99% confidence interval for the monthly sales of one month with a 10% interest rate.

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Definitions:

Oral Contract

An agreement between parties that is spoken and not formally recorded in written form, yet is legally binding.

Enforceable

Capable of being imposed or executed in accordance with the law.

Bilateral Contract

An agreement featuring mutual obligations, where each party promises to perform an act in exchange for the other party's act.

Self-Service Gas Station

A fuel station where customers pump their own gasoline instead of being assisted by an attendant.