Question

A sample of 17 randomly selected student cars have ages with a mean of 7.8 years and a standard deviation of 3.6 years, while a sample of 22 randomly selected faculty cars have ages with a mean of 5.6 years and a standard deviation of 3.3 years.

1. Use a 0.05 significance level to test the claim that student cars are older than faculty cars.

(a) The test statistic is 1.9619

(b) The critical value is 1.688

(c) Is there sufficient evidence to support the claim that student cars are older than faculty cars?

Yes



2. Construct a 95% confidence interval estimate of the difference μs−μf, where μsμs is the mean age of student cars and μf is the mean age of faculty cars.
_______ <(μs−μf)< _______

Answer 1