Выполни действия с дробями: 8) 11/16 + 3/40, 9) 23/50 + 25/30, 10) 20/51 + 31/34, 3) 8/21 - 1/6, 4) 13/33 - 5/22, 5) 3/4 - 7/18

8) \( \frac{11}{16} + \frac{3}{40} = \frac{11 \cdot 5}{16 \cdot 5} + \frac{3 \cdot 2}{40 \cdot 2} = \frac{55}{80} + \frac{6}{80} = \frac{55 + 6}{80} = \frac{61}{80} \) 9) \( \frac{23}{50} + \frac{25}{30} = \frac{23 \cdot 3}{50 \cdot 3} + \frac{25 \cdot 5}{30 \cdot 5} = \frac{69}{150} + \frac{125}{150} = \frac{69 + 125}{150} = \frac{194}{150} = \frac{97}{75} = 1 \frac{22}{75} \) 10) \( \frac{20}{51} + \frac{31}{34} = \frac{20 \cdot 34}{51 \cdot 34} + \frac{31 \cdot 51}{34 \cdot 51} = \frac{680}{1734} + \frac{1581}{1734} = \frac{680 + 1581}{1734} = \frac{2261}{1734} \) 3) \( \frac{8}{21} - \frac{1}{6} = \frac{8 \cdot 2}{21 \cdot 2} - \frac{1 \cdot 7}{6 \cdot 7} = \frac{16}{42} - \frac{7}{42} = \frac{16 - 7}{42} = \frac{9}{42} = \frac{3}{14} \) 4) \( \frac{13}{33} - \frac{5}{22} = \frac{13 \cdot 2}{33 \cdot 2} - \frac{5 \cdot 3}{22 \cdot 3} = \frac{26}{66} - \frac{15}{66} = \frac{26 - 15}{66} = \frac{11}{66} = \frac{1}{6} \) 5) \( \frac{3}{4} - \frac{7}{18} = \frac{3 \cdot 9}{4 \cdot 9} - \frac{7 \cdot 2}{18 \cdot 2} = \frac{27}{36} - \frac{14}{36} = \frac{27 - 14}{36} = \frac{13}{36} \)