Use the following to answer the question(s) below.
A sample of 30 year fixed mortgage rates at 12 randomly chosen credit unions yields a mean rate of 6.65 % and a sample standard deviation of 0.39%. A sample of 30 year fixed mortgage rates at 16 randomly selected banks yields a mean rate of 7.05% and a sample standard deviation of 0.22%. Are the mean rates different between credit unions and banks? Relevant output is shown below.
-Which of the following is true?
A) This is a paired design.
B) This is a test of two means from independent samples.
C) This is a one-tailed test.
D) This is a paired design and this is a one-tailed test.
E) This is a test of two means from independent samples and this is a one-tailed test.

Question

Use the following to answer the question(s) below.
A sample of 30 year fixed mortgage rates at 12 randomly chosen credit unions yields a mean rate of 6.65 % and a sample standard deviation of 0.39%. A sample of 30 year fixed mortgage rates at 16 randomly selected banks yields a mean rate of 7.05% and a sample standard deviation of 0.22%. Are the mean rates different between credit unions and banks? Relevant output is shown below. 
-Which of the following is true?
A) This is a paired design. 
B) This is a test of two means from independent samples. 
C) This is a one-tailed test. 
D) This is a paired design and this is a one-tailed test. 
E) This is a test of two means from independent samples and this is a one-tailed test.

Quizplus · Accepted Answer

The question is asking if the mean rates are different between two independent samples, credit unions and banks. Therefore, this is a test of two means from independent samples. There is no mention of the samples being paired, so A and D are incorrect. There is also no indication that this is a one-tailed test, so C and D are incorrect. E is partially correct, but it only identifies one aspect of the question (test of two means from independent samples) and is incorrect in stating that it is a one-tailed test.

Use the Following to Answer the Question(s) Below