Question

You are interested in determining whether the grades of current high school students in Grand Forks are different than the grades of past students. The state board of education is able to tell you that the mean GPA for students graduating in Grand Forks in the past 40 years is 2.82, but that is all the information they have. You randomly select 90 students who are about to graduate and compute their mean GPA. Which statistical test will tell you if there is a difference in GPA between the current students and students from the past 40 years?

		related samples t test
		z-score for sample means (single sample z test)
		single sample t test
		independent measures t test

Answer 1

Answer: Single sample t test

single sample t test

Explanation:

For the given scenario, the null and alternative hypotheses are given as below:

Null hypothesis: H0: The average GPA of the current students is 2.82.

Alternative hypothesis: Ha: The average GPA of the current students is different from 2.82.

Here, we have to check the claim regarding single population mean.

So we need to use one sample t test for the population mean because we are not given the value for the population standard deviation.