Выполни, пожалуйста, сложение в примере под буквой а)

1. Выполним сложение: a) $\frac{4}{9} + \frac{3}{5} = \frac{4 \cdot 5 + 3 \cdot 9}{9 \cdot 5} = \frac{20 + 27}{45} = \frac{47}{45} = 1\frac{2}{45}$ б) $\frac{7}{18} + \frac{7}{12} = \frac{7 \cdot 2 + 7 \cdot 3}{36} = \frac{14 + 21}{36} = \frac{35}{36}$ в) $\frac{11}{25} + \frac{13}{30} = \frac{11 \cdot 6 + 13 \cdot 5}{150} = \frac{66 + 65}{150} = \frac{131}{150}$ г) $\frac{5}{38} + \frac{7}{19} = \frac{5 + 7 \cdot 2}{38} = \frac{5 + 14}{38} = \frac{19}{38} = \frac{1}{2}$ 2. Выполним вычитание: a) $\frac{1}{11} - \frac{1}{33} = \frac{3 - 1}{33} = \frac{2}{33}$ б) $\frac{7}{11} - \frac{5}{8} = \frac{7 \cdot 8 - 5 \cdot 11}{88} = \frac{56 - 55}{88} = \frac{1}{88}$ в) $\frac{13}{30} - \frac{2}{45} = \frac{13 \cdot 3 - 2 \cdot 2}{90} = \frac{39 - 4}{90} = \frac{35}{90} = \frac{7}{18}$ г) $\frac{13}{60} - \frac{7}{40} = \frac{13 \cdot 2 - 7 \cdot 3}{120} = \frac{26 - 21}{120} = \frac{5}{120} = \frac{1}{24}$ 3. Выполним действия: a) $4\frac{1}{6} + 3\frac{2}{5} = \frac{25}{6} + \frac{17}{5} = \frac{25 \cdot 5 + 17 \cdot 6}{30} = \frac{125 + 102}{30} = \frac{227}{30} = 7\frac{17}{30}$ б) $8\frac{3}{4} - 7\frac{5}{6} = \frac{35}{4} - \frac{47}{6} = \frac{35 \cdot 3 - 47 \cdot 2}{12} = \frac{105 - 94}{12} = \frac{11}{12}$ в) $2\frac{11}{12} + 6\frac{5}{8} = \frac{35}{12} + \frac{53}{8} = \frac{35 \cdot 2 + 53 \cdot 3}{24} = \frac{70 + 159}{24} = \frac{229}{24} = 9\frac{13}{24}$ г) $2\frac{13}{14} - 1\frac{20}{21} = \frac{41}{14} - \frac{41}{21} = \frac{41 \cdot 3 - 41 \cdot 2}{42} = \frac{123 - 82}{42} = \frac{41}{42}$ 4. Выполним умножение: a) $\frac{3}{8} \cdot \frac{9}{11} = \frac{3 \cdot 9}{8 \cdot 11} = \frac{27}{88}$ б) $\frac{22}{35} \cdot \frac{21}{44} = \frac{22 \cdot 21}{35 \cdot 44} = \frac{1 \cdot 3}{5 \cdot 2} = \frac{3}{10}$ в) $5\frac{3}{5} \cdot 1\frac{4}{21} = \frac{28}{5} \cdot \frac{25}{21} = \frac{4}{1} \cdot \frac{5}{3} = \frac{20}{3} = 6\frac{2}{3}$ г) $9\frac{3}{7} \cdot 1\frac{3}{11} = \frac{66}{7} \cdot \frac{14}{11} = \frac{6}{1} \cdot \frac{2}{1} = 12$ д) $1\frac{1}{15} \cdot \frac{5}{16} = \frac{16}{15} \cdot \frac{5}{16} = \frac{1}{3} \cdot \frac{1}{1} = \frac{1}{3}$ е) $2\frac{7}{11} \cdot 2\frac{5}{14} = \frac{29}{11} \cdot \frac{33}{14} = \frac{29}{1} \cdot \frac{3}{14} = \frac{87}{14} = 6\frac{3}{14}$ 5. Выполним деление: a) $\frac{6}{25} : \frac{9}{5} = \frac{6}{25} \cdot \frac{5}{9} = \frac{2}{5} \cdot \frac{1}{3} = \frac{2}{15}$ б) $\frac{8}{27} : \frac{8}{9} = \frac{8}{27} \cdot \frac{9}{8} = \frac{1}{3} \cdot \frac{1}{1} = \frac{1}{3}$ в) $6\frac{2}{3} : 1\frac{1}{8} = \frac{20}{3} : \frac{9}{8} = \frac{20}{3} \cdot \frac{8}{9} = \frac{160}{27} = 5\frac{25}{27}$ г) $\frac{36}{47} : 18 = \frac{36}{47} \cdot \frac{1}{18} = \frac{2}{47} \cdot \frac{1}{1} = \frac{2}{47}$