3. Решите уравнения: a) \(2\frac{1}{6} - \left(x + 1\frac{1}{12}\right) = 0,25; б) 8\frac{1}{3} - \left(5\frac{2}{15} - x\right) = 3\frac{2}{9}\).

3. Решение уравнений:

1. а)
   \(2\frac{1}{6} - \left(x + 1\frac{1}{12}\right) = 0,25\)
   \(\frac{13}{6} - \left(x + \frac{13}{12}\right) = \frac{1}{4}\)
   \(x + \frac{13}{12} = \frac{13}{6} - \frac{1}{4}\)
   Приведём к общему знаменателю 12:
   \(x + \frac{13}{12} = \frac{13 \cdot 2}{12} - \frac{1 \cdot 3}{12}\)
   \(x + \frac{13}{12} = \frac{26 - 3}{12}\)
   \(x + \frac{13}{12} = \frac{23}{12}\)
   \(x = \frac{23}{12} - \frac{13}{12}\)
   \(x = \frac{10}{12} = \frac{5}{6}\)
2. б)
   \(8\frac{1}{3} - \left(5\frac{2}{15} - x\right) = 3\frac{2}{9}\)
   \(\frac{25}{3} - \left(\frac{77}{15} - x\right) = \frac{29}{9}\)
   \(\frac{77}{15} - x = \frac{25}{3} - \frac{29}{9}\)
   Приведём к общему знаменателю 9:
   \(\frac{77}{15} - x = \frac{25 \cdot 3}{9} - \frac{29}{9}\)
   \(\frac{77}{15} - x = \frac{75 - 29}{9}\)
   \(\frac{77}{15} - x = \frac{46}{9}\)
   \(x = \frac{77}{15} - \frac{46}{9}\)
   Приведём к общему знаменателю 45:
   \(x = \frac{77 \cdot 3}{45} - \frac{46 \cdot 5}{45}\)
   \(x = \frac{231 - 230}{45}\)
   \(x = \frac{1}{45}\)

Ответ: а) \(x = \frac{5}{6}\); б) \(x = \frac{1}{45}\).