For a 4-unit class like Statistics, students should spend average of 12 hours studying for the class. A survey was done on 22 students, and the distribution of total study hours per week is...

Extracted text: For a 4-unit class like Statistics, students should spend average of 12 hours studying for the class. A survey was done on 22 students, and the distribution of total study hours per week is bell-shaped with a mean of 12 hours and a standard deviation of 2.8 hours. Use the Empirical Rule to answer the following questions. a) 68% of the students spend between 9.215 on Statistics each week. Xhours and 14.785 hours b) 95% of the students spend between 6.512 X hours and 6.512 X hours on Statistics each week. c) 99.7% of the students spend between 20.288 x hours and 20.288 x hours on Statistics each week.