Помогите пожалуйста

1) $\frac{1}{3} = \frac{4}{12}$
$\frac{7}{12} - [tex] \frac{4}{12}= \frac{3}{12}$
$\frac{1}{2} = \frac{5}{10}$
$\frac{2}{5} = \frac{4}{10}$
$\frac{5}{10} - [tex] \frac{4}{10}= \frac{1}{10}$
\frac{3}{12} [/tex] / \frac{1}{10} [/tex]=\frac{30}{12} [/tex]=\frac{5}{2} [/tex]
2) \frac{3}{5} = \frac{9}{15}
\frac{9}{15} - \frac{4}{15} = \frac{5}{15}
\frac{1}{2} = \frac{2}{4}
\frac{3}{4} - \frac{2}{4} = \frac{1}{4}
\frac{5}{15}/ \frac{1}{4} = \frac{5}{15} * \frac{4}{1} = \frac{20}{15} = \frac{4}{3}
3) \frac{1}{4} = \frac{2}{8}
\frac{1}{8}+\frac{2}{8}=\frac{3}{8}
\frac{2}{3}= \frac{4}{6}
\frac{5}{6} + \frac{4}{6} = \frac{9}{6}
\frac{3}{8} / \frac{9}{6} = \frac{18}{72} = \frac{3}{12} = \frac{1}{4}
4) \frac{1}{6} = \frac{3}{18}
\frac{7}{18} + \frac{3}{18} = \frac{10}{18}
2 \frac{1}{2} = \frac{5}{2} = \frac{15}{6}
\frac{15}{6} + \frac{5}{6} = \frac{20}{6}
\frac{10}{18} / \frac{20}{6} = \frac{60}{360} = \frac{1}{6}