9.25 A statistics instructor is interested in the ability of students to assess the difficulty of a test they have taken.

This test was taken by a large group of students, and the average score was 80.3. A random sample of eight students was asked to predict this average score. Their predictions were as follows:

77 88 73 61 62 79 97 75 Assuming a normal distribution, test the null hypothesis that the population mean prediction would be 80.3. Use a two-sided alternative and a 10% significance level.