Chapter 8, Problem 7P

Babcock and Marks (2010) reviewed survey data from 2003-2005, and obtained an average of $\mu =14$ hours per week spent studying by full-time students at 4-year colleges in the United States. To determine whether this average has changed in the past 10 years, researcher selected a sample of $n=64$ of today’s college students and obtained an average of $M=12.5$ hours. If the standard deviation for the distribution is $\sigma =4.8$ hours per week, does this sample indicate a significant change in the number of hours spent studying? Use a two-tailed test with $\alpha =.05$ .