$$\frac{6^8 \cdot 6^{12}}{6^{18}} + \frac{29^{12}}{29^5 \cdot 29^6} = \frac{6^{8+12}}{6^{18}} + \frac{29^{12}}{29^{5+6}} = \frac{6^{20}}{6^{18}} + \frac{29^{12}}{29^{11}} = 6^{20-18} + 29^{12-11} = 6^2 + 29^1 = 36 + 29 = 65$$
Ответ: 65