Writing the equation $\log_{16} (r+16) = \frac{5}{4}$ in exponential notation gives $r+16 = 16^{\frac{5}{4}} = (2^4)^{\frac{5}{4}} = 2^5 = 32$. Solving $r+16 = 32$ gives $r = \boxed{16}$.
Find the $r$ that satisfies $\log_{16} (r+16) = \frac{5}{4}$.
{'answer': '16', 'subject': 'Algebra', 'level': 3, 'unique_id': 'train/algebra/454.json'}