6.240 Вычислите: a) 4+45; 13+13 б) 73-22; 5 5 6) 7-3 и 9-5. 19 19 16 16 B) 9-5 5 и 39 8 32 14 8 16 r) 6 + 81 12 + 18

Ответ: a) 4\frac{9}{13}; б) 10\frac{1}{5}; в) \frac{4}{19} и \frac{4}{16}; г) \frac{13}{12} и \frac{11}{18}

1. a) \(4 + \frac{4}{13} + \frac{5}{13} = 4 + \frac{4+5}{13} = 4 + \frac{9}{13} = 4\frac{9}{13}\)
2. б) \(7\frac{3}{5} - 2\frac{2}{5} = (7 - 2) + \frac{3}{5} - \frac{2}{5} = 5 + \frac{3-2}{5} = 5 + \frac{1}{5} = 5\frac{1}{5} \)
3. в) \(\frac{7}{19} - \frac{3}{19} = \frac{7-3}{19} = \frac{4}{19}\); \(\frac{9}{16} - \frac{5}{16} = \frac{9-5}{16} = \frac{4}{16}\)
4. г) \(\frac{9}{8} - \frac{5}{32} = \frac{9 \cdot 4}{8 \cdot 4} - \frac{5}{32} = \frac{36}{32} - \frac{5}{32} = \frac{36-5}{32} = \frac{31}{32}\); \(\frac{3}{14} + \frac{9}{8} - \frac{5}{16} = \frac{3 \cdot 8}{14 \cdot 8} + \frac{9 \cdot 14}{8 \cdot 14} - \frac{5 \cdot 7}{16 \cdot 7} = \frac{24}{112} + \frac{126}{112} - \frac{35}{112} = \frac{24 + 126 - 35}{112} = \frac{115}{112} = 1\frac{3}{112}\)
5. д) \(\frac{6}{12} + \frac{8}{18} = \frac{6 \cdot 3}{12 \cdot 3} + \frac{8 \cdot 2}{18 \cdot 2} = \frac{18}{36} + \frac{16}{36} = \frac{18 + 16}{36} = \frac{34}{36} = \frac{17}{18}\); \(\frac{1}{12} + \frac{8}{18} = \frac{1 \cdot 3}{12 \cdot 3} + \frac{8 \cdot 2}{18 \cdot 2} = \frac{3}{36} + \frac{16}{36} = \frac{3 + 16}{36} = \frac{19}{36}\)

Ответ: a) 4\frac{9}{13}; б) 10\frac{1}{5}; в) \frac{4}{19} и \frac{4}{16}; г) \frac{13}{12} и \frac{11}{18}