8) 4 1/7 - 2 4/7 =

8) $$\begin{aligned}4\frac{1}{7} - 2\frac{4}{7} &= 3 + \frac{7}{7} + \frac{1}{7} - 2\frac{4}{7} = 3 + \frac{8}{7} - 2 - \frac{4}{7} = 1\frac{4}{7}\\\\&=\frac{1 \cdot 7 + 4}{7} = \frac{7+4}{7} = \frac{11}{7} = 1\frac{4}{7}\end{aligned}$$

Ответ: 1 4/7