3. Решить уравнение: 8 5 1) 9 - y = 27 7 5 2) b+212 = 1112

3. Решить уравнение:

1) $$ \frac{8}{9} - y = \frac{5}{27} $$

$$ y = \frac{8}{9} - \frac{5}{27} $$

$$ y = \frac{8 \cdot 3}{9 \cdot 3} - \frac{5}{27} $$

$$ y = \frac{24}{27} - \frac{5}{27} $$

$$ y = \frac{24-5}{27} $$

$$ y = \frac{19}{27} $$

2) $$ b + 2\frac{7}{12} = 11\frac{5}{12} $$

$$ b = 11\frac{5}{12} - 2\frac{7}{12} $$

$$ b = (11 - 2) + (\frac{5}{12} - \frac{7}{12}) $$

$$ b = 9 + (\frac{5}{12} - \frac{7}{12}) $$

$$ b = 9 - \frac{2}{12} $$

$$ b = 8\frac{12}{12} - \frac{2}{12} $$

$$ b = 8\frac{10}{12} = 8\frac{5}{6} $$

Ответ: 1) $$\frac{19}{27}$$, 2) $$8\frac{5}{6}$$