Решение:
- \( \frac{7}{15} + \frac{2}{15} = \frac{7+2}{15} = \frac{9}{15} = \frac{3}{5} \)
- \( \frac{37}{46} - \frac{21}{46} = \frac{37-21}{46} = \frac{16}{46} = \frac{8}{23} \)
- \( \frac{5}{36} + \frac{17}{36} = \frac{5+17}{36} = \frac{22}{36} = \frac{11}{18} \)
- \( \frac{17}{63} - \frac{32}{63} = \frac{17-32}{63} = \frac{-15}{63} = \frac{-5}{21} \)
Ответ: 1) \(\frac{3}{5}\); 2) \(\frac{8}{23}\); 3) \(\frac{11}{18}\); 4) \(\frac{-5}{21}\).