1. Ответ: 2/3

[tex]x + 1 \frac{7}{9} = 2 \frac{4}{9} \\ x + \frac{16}{9} = \frac{22}{9} \\ x = \frac{22}{9} - \frac{16}{9} = \frac{6}{9} = \frac{2}{3} [/tex]

2. Ответ: 10целых8/9

[tex]12 - x = 1 \frac{1}{9} \\ x = 12 - 1 \frac{1}{9} \\ x = 11 \frac{9}{9} - 1 \frac{1}{9} = 10 \frac{8}{9} [/tex]