Final answer:
Susan babysat for 15 hours last week.
Step-by-step explanation:
To determine how many hours Susan babysat last week, let's set up equations based on the given information. Let B represent the number of hours she babysat and H represent the number of hours she worked as a hostess. We know that Susan makes $875 per hour as a hostess and $10 per hour babysitting, and she made a total of $165 last week.
From the given information, we can set up the equations:
- H - B = 6 (She worked 6 hours more as a hostess than she did babysitting)
- 875H + 10B = 165 (The total amount she made last week)
We can now solve these equations to find the value of B, the number of hours she babysat last week. Solving these equations gives us B = 15 hours.
Therefore, Susan babysat for 15 hours last week.