63. Упростите выражение: 1) \(\frac{2}{15}a + \frac{3}{12}b - \frac{7}{12}b\); 2) \(14 \frac{5}{9}a - 3 \frac{7}{9}a - 5 \frac{5}{9}a\).

\(\frac{2}{15}a + \frac{3}{12}b - \frac{7}{12}b = \frac{2}{15}a + (\frac{3}{12} - \frac{7}{12})b = \frac{2}{15}a + (\frac{3 - 7}{12})b = \frac{2}{15}a + (\frac{-4}{12})b = \frac{2}{15}a - \frac{1}{3}b\)

Ответ: \(\frac{2}{15}a - \frac{1}{3}b\)

\(14 \frac{5}{9}a - 3 \frac{7}{9}a - 5 \frac{5}{9}a = (14 \frac{5}{9} - 3 \frac{7}{9} - 5 \frac{5}{9})a = (14 - 3 - 5 + \frac{5}{9} - \frac{7}{9} - \frac{5}{9})a = (6 + \frac{5 - 7 - 5}{9})a = (6 + \frac{-7}{9})a = (6 - \frac{7}{9})a = (5 + 1 - \frac{7}{9})a = (5 + \frac{9}{9} - \frac{7}{9})a = (5 + \frac{2}{9})a = 5 \frac{2}{9}a\)

Ответ: \(5 \frac{2}{9}a\)