№3 Вычислите: $$\frac{\frac{15}{39}+\frac{39}{10}}{\frac{100}{21}}$$

$$\frac{\frac{15}{39}+\frac{39}{10}}{\frac{100}{21}}=\frac{\frac{150+1521}{390}}{\frac{100}{21}}=\frac{\frac{1671}{390}}{\frac{100}{21}}=\frac{1671}{390} \cdot \frac{21}{100}=\frac{1671 \cdot 21}{390 \cdot 100}=\frac{35091}{39000}=\frac{11697}{13000}$$ Ответ: $$\frac{11697}{13000}$$