Two health clubs, FitCo and StrongGym, charge monthly according to linear models in the number of group classes attended, m.
- FitCo: F(m)=38+12m where F(m) is the total monthly cost, in dollars.
- StrongGym: a flat monthly fee plus $15 per class.
If the monthly cost is the same at both clubs when m=4, what is the flat monthly fee, in dollars, that StrongGym charges?