13)+

$$\frac{7}{8}+\frac{1}{3} = \frac{7 \cdot 3}{8 \cdot 3}+\frac{1 \cdot 8}{3 \cdot 8} = \frac{21}{24}+\frac{8}{24} = \frac{29}{24} = 1\frac{5}{24}$$

Ответ: $$1\frac{5}{24}$$