Final answer:
A student taking a three credit hour class should allocate up to nine additional hours for study and assignments per week, following the common guideline of two to three hours outside class for every hour spent in class.
Step-by-step explanation:
A student who is taking one class for a total of three credit hours should plan to spend up to nine additional hours per week on school-related work. This is often based on the general guideline that students should spend approximately two to three hours studying and completing assignments for every one hour of class time. Given that students' study needs may vary, some may find they need to spend more or less time outside of class. Statistical data also reveals various study habits among students. However, as a baseline, allocating additional hours in proportion to the credit hours is a standard academic practice.