1. **State the problem:** Solve for $f$ in the equation $$\frac{f}{3} + 12 = 17.$$\n\n2. **Isolate the term $\frac{f}{3}$:** To isolate $\frac{f}{3}$, subtract 12 from both sides:\n$$\frac{f}{3} + 12 - 12 = 17 - 12$$\n$$\frac{f}{3} = 5.$$\n\n3. **Solve for $f$:** Multiply both sides by 3 to get rid of the denominator:\n$$3 \times \frac{f}{3} = 3 \times 5$$\n$$\cancel{3} \times \frac{f}{\cancel{3}} = 15$$\n$$f = 15.$$\n\n**Final answer:** $f = 15$.