2. a) $$\frac{3}{10} \cdot \frac{5}{7} + \frac{11}{14}$$

$$\frac{3}{10} \cdot \frac{5}{7} + \frac{11}{14} = $$ Сокращаем первую дробь: $$\frac{3}{\cancel{10}^2} \cdot \frac{\cancel{5}}{7} + \frac{11}{14} = $$ $$\frac{3}{2} \cdot \frac{1}{7} + \frac{11}{14} = $$ $$\frac{3 \cdot 1}{2 \cdot 7} + \frac{11}{14} = $$ $$\frac{3}{14} + \frac{11}{14} = $$ $$\frac{3 + 11}{14} = $$ $$\frac{14}{14} = $$ $$\frac{\cancel{14}}{\cancel{14}} = 1$$ Ответ: $$\boxed{1}$$