3. Выполните действия: a) \(4 \frac{7}{10} + 1 \frac{8}{15}\); б) \(3 \frac{3}{14} + 1 \frac{4}{63}\); в) \(4 \frac{4}{15} - 2 \frac{9}{40}\); г) \(5 \frac{1}{20} - 2 \frac{1}{12}\)

3. Выполните действия: а) \(4 \frac{7}{10} + 1 \frac{8}{15} = 4 + 1 + \frac{7}{10} + \frac{8}{15} = 5 + \frac{7 \cdot 3 + 8 \cdot 2}{30} = 5 + \frac{21 + 16}{30} = 5 + \frac{37}{30} = 5 + 1 \frac{7}{30} = 6 \frac{7}{30}\) б) \(3 \frac{3}{14} + 1 \frac{4}{63} = 3 + 1 + \frac{3}{14} + \frac{4}{63} = 4 + \frac{3 \cdot 9 + 4 \cdot 2}{126} = 4 + \frac{27 + 8}{126} = 4 + \frac{35}{126} = 4 + \frac{5}{18} = 4 \frac{5}{18}\) в) \(4 \frac{4}{15} - 2 \frac{9}{40} = 4 - 2 + \frac{4}{15} - \frac{9}{40} = 2 + \frac{4 \cdot 8 - 9 \cdot 3}{120} = 2 + \frac{32 - 27}{120} = 2 + \frac{5}{120} = 2 + \frac{1}{24} = 2 \frac{1}{24}\) г) \(5 \frac{1}{20} - 2 \frac{1}{12} = 5 - 2 + \frac{1}{20} - \frac{1}{12} = 3 + \frac{1 \cdot 3 - 1 \cdot 5}{60} = 3 + \frac{3 - 5}{60} = 3 - \frac{2}{60} = 3 - \frac{1}{30} = 2 \frac{29}{30}\)