Помогите пожалуйста по математике номер 834

[latex]1) \frac{11}{22}= \frac{1}{2}, \frac{10}{25}= \frac{2}{5}, \frac{27}{45}= \frac{3}{5}, \frac{9}{12}= \frac{3}{4}; [/latex] [latex]2) \frac{15}{18}= \frac{5}{6},\frac{24}{30}=\frac{4}{5},\frac{28}{32}=\frac{7}{8},\frac{21}{15}=\frac{7}{5}; [/latex] [latex]3)\frac{75}{45}=\frac{5}{3},\frac{38}{66}=\frac{19}{33},\frac{54}{90}=\frac{6}{10}=\frac{3}{5},\frac{36}{84}=\frac{6}{14}=\frac{3}{7}; [/latex] [latex]4)\frac{49}{56}=\frac{7}{8},\frac{55}{77}=\frac{5}{7},\frac{26}{65}=\frac{2}{5},\frac{51}{85}=\frac{3}{5}. [/latex]