24. Вычислите: a) \( \frac{5}{6} + \frac{2}{7} = \) б) \( \frac{11}{25} - \frac{3}{10} = \) г) \( \frac{3}{20} + \frac{7}{15} = \) д) \( \frac{13}{16} - \frac{7}{12} = \) e) \( \frac{9}{14} + \frac{5}{21} = \) б) \( \frac{15}{16} - \frac{3}{4} = \)

24. Решение:

а) \( \frac{5}{6} + \frac{2}{7} = \frac{5 \cdot 7}{6 \cdot 7} + \frac{2 \cdot 6}{7 \cdot 6} = \frac{35}{42} + \frac{12}{42} = \frac{35 + 12}{42} = \frac{47}{42} = 1 \frac{5}{42} \)

б) \( \frac{11}{25} - \frac{3}{10} = \frac{11 \cdot 2}{25 \cdot 2} - \frac{3 \cdot 5}{10 \cdot 5} = \frac{22}{50} - \frac{15}{50} = \frac{22 - 15}{50} = \frac{7}{50} \)

г) \( \frac{3}{20} + \frac{7}{15} = \frac{3 \cdot 3}{20 \cdot 3} + \frac{7 \cdot 4}{15 \cdot 4} = \frac{9}{60} + \frac{28}{60} = \frac{9 + 28}{60} = \frac{37}{60} \)

д) \( \frac{13}{16} - \frac{7}{12} = \frac{13 \cdot 3}{16 \cdot 3} - \frac{7 \cdot 4}{12 \cdot 4} = \frac{39}{48} - \frac{28}{48} = \frac{39 - 28}{48} = \frac{11}{48} \)

е) \( \frac{9}{14} + \frac{5}{21} = \frac{9 \cdot 3}{14 \cdot 3} + \frac{5 \cdot 2}{21 \cdot 2} = \frac{27}{42} + \frac{10}{42} = \frac{27 + 10}{42} = \frac{37}{42} \)

б) \( \frac{15}{16} - \frac{3}{4} = \frac{15}{16} - \frac{3 \cdot 4}{4 \cdot 4} = \frac{15}{16} - \frac{12}{16} = \frac{15 - 12}{16} = \frac{3}{16} \)

Ответ: а) \( 1 \frac{5}{42} \); б) \( \frac{7}{50} \); г) \( \frac{37}{60} \); д) \( \frac{11}{48} \); е) \( \frac{37}{42} \); б) \( \frac{3}{16} \).