10) 3 15 7 +-= 20 Выполните вычитание Вариант 2 11 1) 7- = 20 50 17 5 2) - = 33 22 9 5 3) - = 20 8 4 13 4) - = 7 28 5 14 5) - = 13 39 5 2 6) - = 8 7 3 12 7) - = 4 5 15 27 8) - = 23 46 9 14 9) - = 25 117 17 13 10) - = 35 28

$$10) \frac{3}{15} + \frac{7}{20} = \frac{3 \cdot 4}{15 \cdot 4} + \frac{7 \cdot 3}{20 \cdot 3} = \frac{12}{60} + \frac{21}{60} = \frac{12+21}{60} = \frac{33}{60} = \frac{11}{20}$$

Выполните вычитание Вариант 2

1. $$1) \frac{7}{20} - \frac{11}{50} = \frac{7 \cdot 5}{20 \cdot 5} - \frac{11 \cdot 2}{50 \cdot 2} = \frac{35}{100} - \frac{22}{100} = \frac{35 - 22}{100} = \frac{13}{100}$$
2. $$2) \frac{17}{33} - \frac{5}{22} = \frac{17 \cdot 2}{33 \cdot 2} - \frac{5 \cdot 3}{22 \cdot 3} = \frac{34}{66} - \frac{15}{66} = \frac{34-15}{66} = \frac{19}{66}$$
3. $$3) \frac{9}{20} - \frac{5}{8} = \frac{9 \cdot 2}{20 \cdot 2} - \frac{5 \cdot 5}{8 \cdot 5} = \frac{18}{40} - \frac{25}{40} = \frac{18-25}{40} = -\frac{7}{40}$$
4. $$4) \frac{4}{7} - \frac{13}{28} = \frac{4 \cdot 4}{7 \cdot 4} - \frac{13}{28} = \frac{16}{28} - \frac{13}{28} = \frac{16-13}{28} = \frac{3}{28}$$
5. $$5) \frac{5}{13} - \frac{14}{39} = \frac{5 \cdot 3}{13 \cdot 3} - \frac{14}{39} = \frac{15}{39} - \frac{14}{39} = \frac{15-14}{39} = \frac{1}{39}$$
6. $$6) \frac{5}{8} - \frac{2}{7} = \frac{5 \cdot 7}{8 \cdot 7} - \frac{2 \cdot 8}{7 \cdot 8} = \frac{35}{56} - \frac{16}{56} = \frac{35-16}{56} = \frac{19}{56}$$
7. $$7) \frac{3}{4} - \frac{12}{5} = \frac{3 \cdot 5}{4 \cdot 5} - \frac{12 \cdot 4}{5 \cdot 4} = \frac{15}{20} - \frac{48}{20} = \frac{15-48}{20} = -\frac{33}{20}$$
8. $$8) \frac{15}{23} - \frac{27}{46} = \frac{15 \cdot 2}{23 \cdot 2} - \frac{27}{46} = \frac{30}{46} - \frac{27}{46} = \frac{30-27}{46} = \frac{3}{46}$$
9. $$9) \frac{9}{25} - \frac{14}{117} = \frac{9 \cdot 117}{25 \cdot 117} - \frac{14 \cdot 25}{117 \cdot 25} = \frac{1053}{2925} - \frac{350}{2925} = \frac{1053-350}{2925} = \frac{703}{2925}$$
10. $$10) \frac{17}{35} - \frac{13}{28} = \frac{17 \cdot 4}{35 \cdot 4} - \frac{13 \cdot 5}{28 \cdot 5} = \frac{68}{140} - \frac{65}{140} = \frac{68-65}{140} = \frac{3}{140}$$

Ответ: 1) 13/100; 2) 19/66; 3) -7/40; 4) 3/28; 5) 1/39; 6) 19/56; 7) -33/20; 8) 3/46; 9) 703/2925; 10) 3/140