Compute the p-value

Question

Question 1. Independent random samples taken on two university campuses revealed the following information concerning the average amount of money spent on non-textbook purchases at the university's bookstore during the fall semester.

		University A	University B
	Sample Size	50	40
	Average Purchase	$260	$250
	Population Standard Deviation(σ)	$20	$23

We want to determine if, on the average, students at University A spent more on non-textbook purchases at the university's bookstore than the students at University B.

a.  Compute the test statistic.

b.  Compute the p-value.

c.  What is your conclusion? Let α = .05.

Question 2 In a residual plot against x that does not suggest we should challenge the assumptions of our regression model, we would expect to see

		a horizontal band of points centered near zero
		a widening band of points
		a band of points having a slope consistent with that of the regression equation
		a parabolic band of points

Question 3. If we are testing for the equality of 3 population means, we should use the

		test statistic t
		test statistics z
		test statistic χ 2
		test statistic F

Question 4. The expected value of mean equals to the mean of the population from which the sample is drawn

		only if the sample size is 100 or greater
		for any sample size
		only if the sample size is 50 or greater
		only if the sample size is 30 or greater

 

Question 5. A simple random sample of size n from a finite population of size N is to be selected. Each possible sample should have

		a probability of 1/n of being selected
		the same probability of being selected
		a probability of 1/N of being selected
		a probability of N/n of being selected