Ответ:

[tex]\displaystyle(2\frac{1}{4} +4\frac{5}{6} ):3\frac{2}{5} -\frac{3}{4} :\frac{3}{5} =\frac{5}{6}[/tex]

Пошаговое объяснение:

[tex]\displaystyle1)2\frac{1}{4} +4\frac{5}{6} =\frac{9}{4} +\frac{29}{6} =\frac{27}{12} +\frac{58}{12} =\frac{85}{12}[/tex]

[tex]\displaystyle2) \frac{85}{12} :3\frac{2}{5} =\frac{85}{12} :\frac{17}{5} =\frac{85}{12} *\frac{5}{17} =\frac{25}{12}[/tex]

[tex]3)\displaystyle-\frac{3}{4} :\frac{3}{5} =-\frac{3}{4} *\frac{5}{3} =-\frac{5}{4}[/tex]

[tex]\displaystyle4)\frac{25}{12} -\frac{5}{4} =\frac{25}{12} -\frac{15}{12} =\frac{10}{12} =\frac{5}{6}[/tex]