Question

Randomly selected 2020 student cars (population 1) have ages with a mean of 77 years and a standard deviation of 3.63.6 years, while randomly selected 2222 faculty cars (population 2) have ages with a mean of 55 years and a standard deviation of 3.73.7 years. (For the purposes of this exercise, the two populations are assumed to be normally distributed.)

1.    Use a 0.030.03 significance level to test the claim that student cars are older than faculty cars.
The test statistic is
The P-value (using the n1+n2-2 degrees-of-freedom) is
Is there sufficient evidence to support the claim that student cars are older than faculty cars?

A. No
B. Yes

2.    Construct a 9797% confidence interval estimate of the difference μ1−μ2μ1−μ2, where μ1μ1 is the mean age of student cars and μ2μ2 is the mean age of faculty cars. (Use the using the n1+n2-2 degrees-of-freedom formula).  <(μ1−μ2)<<(μ1−μ2)<

Answer 1