Выполните действие а) 3/20•3-3/10:2 б) 1/18•7+5/6:3 в)5/11:2+21/22:3 г) 2/25•10-7/10:2

[latex]a)= \frac{3}{20} *10- \frac{7}{10} * \frac{1}{2} = \frac{3}{10} - \frac{7}{20} = \frac{6-7}{20} =- \frac{1}{20 } \\ b)= \frac{1}{18} *7+ \frac{5}{6} * \frac{1}{3} = \frac{7}{18} + \frac{5}{18}= \frac{12}{18} = \frac{2}{3} \\ B)= \frac{5}{11} * \frac{1}{2} + \frac{21}{22} * \frac{1}{3} = \frac{5}{22}+ \frac{7}{22} = \frac{12}{22} = \frac{6}{11} \\ r)= \frac{2}{25} *10- \frac{7}{10} * \frac{1}{2} = \frac{4}{5} - \frac{7}{20} = \frac{16-7}{20} = \frac{9}{20} [/latex]