1.3. Действия с обыкновенными д Чыполните сложение или вычитание. + 3 8 = 17 5 33 22 = 27-0= 76 9+5 20 8 +=728 5 14 13 39 = 5 8 -2 7 = 3+-4+12 = 1527 23 46 = 914 25 117 = 1713 35 28 = 1-2 7 12 = 6 13 11 40 60 27 160 34 = = 53 12 4 11

Решение:

Выполним сложение дробей:

1) \[\frac{3}{8} + \frac{5}{12} = \frac{3 \cdot 3}{8 \cdot 3} + \frac{5 \cdot 2}{12 \cdot 2} = \frac{9}{24} + \frac{10}{24} = \frac{19}{24}\]

2) \(\frac{17}{33} - \frac{5}{22} = \frac{17 \cdot 2}{33 \cdot 2} - \frac{5 \cdot 3}{22 \cdot 3} = \frac{34}{66} - \frac{15}{66} = \frac{19}{66}\)

3) \(\frac{27}{76} - 0 = \frac{27}{76}\)

4) \(\frac{9}{20} + \frac{5}{8} = \frac{9 \cdot 2}{20 \cdot 2} + \frac{5 \cdot 5}{8 \cdot 5} = \frac{18}{40} + \frac{25}{40} = \frac{43}{40} = 1 \frac{3}{40}\)

5) \(2 \frac{13}{7} + \frac{13}{28} = \frac{2 \cdot 7 + 13}{7} + \frac{13}{28} = \frac{27}{7} + \frac{13}{28} = \frac{27 \cdot 4}{7 \cdot 4} + \frac{13}{28} = \frac{108}{28} + \frac{13}{28} = \frac{121}{28} = 4 \frac{9}{28}\)

6) \(\frac{5}{13} - \frac{14}{39} = \frac{5 \cdot 3}{13 \cdot 3} - \frac{14}{39} = \frac{15}{39} - \frac{14}{39} = \frac{1}{39}\)

7) \(\frac{5}{8} - \frac{2}{7} = \frac{5 \cdot 7}{8 \cdot 7} - \frac{2 \cdot 8}{7 \cdot 8} = \frac{35}{56} - \frac{16}{56} = \frac{19}{56}\)

8) \(\frac{3}{4} + \frac{5}{12} = \frac{3 \cdot 3}{4 \cdot 3} + \frac{5}{12} = \frac{9}{12} + \frac{5}{12} = \frac{14}{12} = \frac{7}{6} = 1 \frac{1}{6}\)

9) \(\frac{15}{23} - \frac{27}{46} = \frac{15 \cdot 2}{23 \cdot 2} - \frac{27}{46} = \frac{30}{46} - \frac{27}{46} = \frac{3}{46}\)

10) \(\frac{9}{25} - \frac{14}{117} = \frac{9 \cdot 117}{25 \cdot 117} - \frac{14 \cdot 25}{117 \cdot 25} = \frac{1053}{2925} - \frac{350}{2925} = \frac{703}{2925}\)

11) \(\frac{17}{35} - \frac{13}{28} = \frac{17 \cdot 4}{35 \cdot 4} - \frac{13 \cdot 5}{28 \cdot 5} = \frac{68}{140} - \frac{65}{140} = \frac{3}{140}\)

12) \(1 - \frac{2}{7} = \frac{7}{7} - \frac{2}{7} = \frac{5}{7}\)

13) \(\frac{13}{40} - \frac{11}{60} = \frac{13 \cdot 3}{40 \cdot 3} - \frac{11 \cdot 2}{60 \cdot 2} = \frac{39}{120} - \frac{22}{120} = \frac{17}{120}\)

14) \(5 \frac{3}{12} + \frac{3}{4} = \frac{5 \cdot 12 + 3}{12} + \frac{3}{4} = \frac{63}{12} + \frac{3}{4} = \frac{63}{12} + \frac{3 \cdot 3}{4 \cdot 3} = \frac{63}{12} + \frac{9}{12} = \frac{72}{12} = 6\)

Ответ: Выше приведены решения.