1 1 + - 9 2 = Полните вычитание Вариант 1 1 3 1) - 2 8 3 5 2) - 7 14 3 4 3) - 5 15 5 3 4) - 8 16 2 1 5) - 9 18 1 1 6) - 13 26 7 7 7) - 15. 30 2 1 8) - 19 38 5 3 9) - 7 14 4 1 10) - 21 7

Выполним вычитание. Вариант 1

1. $$1) \frac{1}{2} - \frac{3}{8} = \frac{1 \cdot 4}{2 \cdot 4} - \frac{3}{8} = \frac{4}{8} - \frac{3}{8} = \frac{4-3}{8} = \frac{1}{8}$$
2. $$2) \frac{3}{7} - \frac{5}{14} = \frac{3 \cdot 2}{7 \cdot 2} - \frac{5}{14} = \frac{6}{14} - \frac{5}{14} = \frac{6-5}{14} = \frac{1}{14}$$
3. $$3) \frac{3}{5} - \frac{4}{15} = \frac{3 \cdot 3}{5 \cdot 3} - \frac{4}{15} = \frac{9}{15} - \frac{4}{15} = \frac{9-4}{15} = \frac{5}{15} = \frac{1}{3}$$
4. $$4) \frac{5}{8} - \frac{3}{16} = \frac{5 \cdot 2}{8 \cdot 2} - \frac{3}{16} = \frac{10}{16} - \frac{3}{16} = \frac{10-3}{16} = \frac{7}{16}$$
5. $$5) \frac{2}{9} - \frac{1}{18} = \frac{2 \cdot 2}{9 \cdot 2} - \frac{1}{18} = \frac{4}{18} - \frac{1}{18} = \frac{4-1}{18} = \frac{3}{18} = \frac{1}{6}$$
6. $$6) \frac{8}{13} - \frac{1}{26} = \frac{8 \cdot 2}{13 \cdot 2} - \frac{1}{26} = \frac{16}{26} - \frac{1}{26} = \frac{16-1}{26} = \frac{15}{26}$$
7. $$7) \frac{7}{15} - \frac{7}{30} = \frac{7 \cdot 2}{15 \cdot 2} - \frac{7}{30} = \frac{14}{30} - \frac{7}{30} = \frac{14-7}{30} = \frac{7}{30}$$
8. $$8) \frac{2}{19} - \frac{1}{38} = \frac{2 \cdot 2}{19 \cdot 2} - \frac{1}{38} = \frac{4}{38} - \frac{1}{38} = \frac{4-1}{38} = \frac{3}{38}$$
9. $$9) \frac{5}{7} - \frac{3}{14} = \frac{5 \cdot 2}{7 \cdot 2} - \frac{3}{14} = \frac{10}{14} - \frac{3}{14} = \frac{10-3}{14} = \frac{7}{14} = \frac{1}{2}$$
10. $$10) \frac{4}{21} - \frac{1}{7} = \frac{4}{21} - \frac{1 \cdot 3}{7 \cdot 3} = \frac{4}{21} - \frac{3}{21} = \frac{4-3}{21} = \frac{1}{21}$$

Ответ: 1) 1/8; 2) 1/14; 3) 1/3; 4) 7/16; 5) 1/6; 6) 15/26; 7) 7/30; 8) 3/38; 9) 1/2; 10) 1/21