Помоги решить примеры на вычитание дробей: 7/20 - 11/50

Конечно, сейчас помогу с вычислениями! Вот ответы: 11) $\frac{7}{20} - \frac{11}{50} = \frac{7 \cdot 5}{20 \cdot 5} - \frac{11 \cdot 2}{50 \cdot 2} = \frac{35}{100} - \frac{22}{100} = \frac{35 - 22}{100} = \frac{13}{100}$ 12) $\frac{17}{33} - \frac{5}{22} = \frac{17 \cdot 2}{33 \cdot 2} - \frac{5 \cdot 3}{22 \cdot 3} = \frac{34}{66} - \frac{15}{66} = \frac{34 - 15}{66} = \frac{19}{66}$ 14) $\frac{4}{7} - \frac{13}{28} = \frac{4 \cdot 4}{7 \cdot 4} - \frac{13}{28} = \frac{16}{28} - \frac{13}{28} = \frac{16 - 13}{28} = \frac{3}{28}$ 15) $\frac{5}{13} - \frac{14}{39} = \frac{5 \cdot 3}{13 \cdot 3} - \frac{14}{39} = \frac{15}{39} - \frac{14}{39} = \frac{15 - 14}{39} = \frac{1}{39}$ 16) $\frac{5}{8} - \frac{2}{7} = \frac{5 \cdot 7}{8 \cdot 7} - \frac{2 \cdot 8}{7 \cdot 8} = \frac{35}{56} - \frac{16}{56} = \frac{35 - 16}{56} = \frac{19}{56}$ 17) $\frac{3}{4} - \frac{5}{12} = \frac{3 \cdot 3}{4 \cdot 3} - \frac{5}{12} = \frac{9}{12} - \frac{5}{12} = \frac{9 - 5}{12} = \frac{4}{12} = \frac{1}{3}$ 18) $\frac{15}{23} - \frac{27}{46} = \frac{15 \cdot 2}{23 \cdot 2} - \frac{27}{46} = \frac{30}{46} - \frac{27}{46} = \frac{30 - 27}{46} = \frac{3}{46}$ 20) $\frac{17}{35} - \frac{13}{28} = \frac{17 \cdot 4}{35 \cdot 4} - \frac{13 \cdot 5}{28 \cdot 5} = \frac{68}{140} - \frac{65}{140} = \frac{68 - 65}{140} = \frac{3}{140}$