1) 3\(\frac{12}{17}\) + 2\(\frac{6}{34}\) = 2) 9-3\(\frac{7}{8}\) = 3) \(\frac{2}{3}\) - \(\frac{5}{9}\) = 4) \(\frac{7}{8}\) + \(\frac{2}{5}\) = 5) \(\frac{2}{5}\) + \(\frac{7}{20}\) = 6) \(\frac{3}{4}\) + \(\frac{1}{20}\) = 7) \(\frac{4}{9}\) - \(\frac{1}{6}\) = 8) \(\frac{1}{2}\) - \(\frac{1}{5}\) = 9) \(\frac{1}{3}\) + \(\frac{1}{4}\) = 10) \(\frac{1}{6}\) + \(\frac{2}{5}\) =

Решение:

1. \( 3\frac{12}{17} + 2\frac{6}{34} = 3\frac{12}{17} + 2\frac{3}{17} = (3+2) + (\frac{12}{17} + \frac{3}{17}) = 5 + \frac{15}{17} = 5\frac{15}{17} \)
2. \( 9 - 3\frac{7}{8} = 8\frac{8}{8} - 3\frac{7}{8} = (8-3) + (\frac{8}{8} - \frac{7}{8}) = 5 + \frac{1}{8} = 5\frac{1}{8} \)
3. \( \frac{2}{3} - \frac{5}{9} = \frac{6}{9} - \frac{5}{9} = \frac{1}{9} \)
4. \( \frac{7}{8} + \frac{2}{5} = \frac{35}{40} + \frac{16}{40} = \frac{51}{40} = 1\frac{11}{40} \)
5. \( \frac{2}{5} + \frac{7}{20} = \frac{8}{20} + \frac{7}{20} = \frac{15}{20} = \frac{3}{4} \)
6. \( \frac{3}{4} + \frac{1}{20} = \frac{15}{20} + \frac{1}{20} = \frac{16}{20} = \frac{4}{5} \)
7. \( \frac{4}{9} - \frac{1}{6} = \frac{8}{18} - \frac{3}{18} = \frac{5}{18} \)
8. \( \frac{1}{2} - \frac{1}{5} = \frac{5}{10} - \frac{2}{10} = \frac{3}{10} \)
9. \( \frac{1}{3} + \frac{1}{4} = \frac{4}{12} + \frac{3}{12} = \frac{7}{12} \)
10. \( \frac{1}{6} + \frac{2}{5} = \frac{5}{30} + \frac{12}{30} = \frac{17}{30} \)

Ответ: 1) \( 5\frac{15}{17} \) 2) \( 5\frac{1}{8} \) 3) \( \frac{1}{9} \) 4) \( 1\frac{11}{40} \) 5) \( \frac{3}{4} \) 6) \( \frac{4}{5} \) 7) \( \frac{5}{18} \) 8) \( \frac{3}{10} \) 9) \( \frac{7}{12} \) 10) \( \frac{17}{30} \)