Originally Posted by

**jpd750** a)

Problem 4: Susan Sound predicts that students will learn most effectively with a constant background sound, as opposed to no sound at all. She randomly divides sixteen students into two groups of eight. All students study a passage of text for 30 minutes. Those in group 1 study with background sound at a constant volume in the background. Those in group 2 study with no sound at all. After studying, all students take a 10 point multiple choice test over the material. Assuming equal population variance, do the data provide sufficient evidence to indicate that the mean scores differ between two groups with a 0.1 significance level? Their scores follow. For the constant sound group: 5, 9, 3, 7, 5, 6, 9, 8. And for the no sound group: 6, 4, 5, 3, 10, 6, 5, 3. A. Assume that the standard deviations are equal and find the test statistic for the test that the between mu1 and mu2 is zero.