10) 2-6

10) $$2 \frac{2}{7} - 6 = \frac{16}{7} - 6 = \frac{16 - 6 \cdot 7}{7} = \frac{16 - 42}{7} = \frac{-26}{7} = -3 \frac{5}{7}$$

Ответ: $$-3 \frac{5}{7}$$