Build a profit function P(h) where h is the number of hours:

P(h) = Hourly Rate * Number of Hours (h) - Cost of Piano

P(h) = 15h - 49

The problem asks for the number of hours where P(h) = $326

15h - 49 = 326

We take this equation and type it in our search engine to solve for h:

h =

**25**