This is Problem 8 from your Section 2.3 (part 2) worksheet.

Sarah wants to do well in her classes, so she's budgeting her time to decide how many classes to take. For each class she takes, she expects to spend $3$ hours every week on homework. She also plans to spend a total of $12$ extra hours studying every week. If Sarah has $24$ hours every week to do homework and studying, how many classes can she take?

She can take classes.

Hint: