Выполните действия: 3. а) 8 8/9 + 2 11/12 - 3 1/4

### 3. Выполните действия: a) $8 \frac{8}{9} + 2 \frac{11}{12} - 3 \frac{1}{4} = 8 \frac{32}{36} + 2 \frac{33}{36} - 3 \frac{9}{36} = 10 \frac{65}{36} - 3 \frac{9}{36} = 7 \frac{56}{36} = 8 \frac{20}{36} = 8 \frac{5}{9}$ б) $7 \frac{5}{8} + 3 \frac{2}{3} - 8 \frac{3}{16} = 7 \frac{15}{24} + 3 \frac{16}{24} - 8 \frac{3}{16} = 10 \frac{31}{24} - 8 \frac{3}{16} = 11 \frac{7}{24} - 8 \frac{3}{16} = 11 \frac{14}{48} - 8 \frac{9}{48} = 3 \frac{5}{48}$ в) $10 - (5 \frac{7}{8} + 3 \frac{5}{12}) = 10 - (5 \frac{21}{24} + 3 \frac{10}{24}) = 10 - 8 \frac{31}{24} = 10 - 9 \frac{7}{24} = 1 - \frac{7}{24} = \frac{17}{24}$ г) $1 \frac{5}{6} + (3 - 1 \frac{7}{10}) = 1 \frac{5}{6} + (2 \frac{10}{10} - 1 \frac{7}{10}) = 1 \frac{5}{6} + 1 \frac{3}{10} = 1 \frac{25}{30} + 1 \frac{9}{30} = 2 \frac{34}{30} = 3 \frac{4}{30} = 3 \frac{2}{15}$ ### 4. Решите уравнения: a) $x + 4 \frac{3}{8} = 6 \frac{1}{8} \implies x = 6 \frac{1}{8} - 4 \frac{3}{8} = 5 \frac{9}{8} - 4 \frac{3}{8} = 1 \frac{6}{8} = 1 \frac{3}{4}$ б) $3 + y = 1 \frac{5}{9} \implies y = 1 \frac{5}{9} - 3 = -1 \frac{4}{9}$ в) $8 - x = 4 \frac{1}{7} \implies x = 8 - 4 \frac{1}{7} = 7 \frac{7}{7} - 4 \frac{1}{7} = 3 \frac{6}{7}$ г) $2 \frac{3}{7} + y = 5 \frac{1}{7} \implies y = 5 \frac{1}{7} - 2 \frac{3}{7} = 4 \frac{8}{7} - 2 \frac{3}{7} = 2 \frac{5}{7}$