5) 2 2/9 - 5/9 =

5) $$\begin{aligned}2\frac{2}{9} - \frac{5}{9} &= 1 + \frac{9}{9} + \frac{2}{9} - \frac{5}{9} = 1 + \frac{11}{9} - \frac{5}{9} = 1\frac{6}{9} = 1\frac{2}{3}\\\\&=\frac{1 \cdot 9 + 6}{9} = \frac{9+6}{9} = \frac{15}{9} = \frac{5}{3} = 1\frac{2}{3}\end{aligned}$$

Ответ: 1 2/3