2. Вычислите: $$(30 : 27 - \frac{1}{7}) \cdot 2\frac{3}{7}$$

$$(30 : 27 - \frac{1}{7}) \cdot 2\frac{3}{7} = (\frac{30}{27} - \frac{1}{7}) \cdot \frac{17}{7} = (\frac{10}{9} - \frac{1}{7}) \cdot \frac{17}{7} = (\frac{70}{63} - \frac{9}{63}) \cdot \frac{17}{7} = \frac{61}{63} \cdot \frac{17}{7} = \frac{1037}{441} = 2\frac{155}{441}$$