Ответ:

Пошаговое объяснение:

[tex]1)\frac{1}{10}+\frac{1}{5} = \frac{1}{10}+\frac{2}{10}=\frac{3}{10} \\ \\ 2)\frac{2}{7} +\frac{1}{3}= \frac{6}{21}+\frac{7}{21}=\frac{13}{21} \\ \\ 3)\frac{1}{3}+\frac{1}{2} =\frac{2}{6} +\frac{3}{6}=\frac{5}{6} \\ \\ 4)\frac{3}{4}-\frac{2}{9}=\frac{27}{36}-\frac{8}{36}=\frac{19}{36}\\ \\ 5)\frac{1}{4} +\frac{5}{6} =\frac{3}{12}+\frac{10}{12} =\frac{13}{12}=1\frac{1}{12} \\ \\[/tex]

[tex]6)\frac{5}{8}-\frac{1}{6} =\frac{15}{24}-\frac{4}{24} =\frac{11}{24} \\ \\ 7)4-\frac{6}{13} =6\frac{13}{13} -\frac{6}{13} =6\frac{7}{13} \\ \\ 8)8-3\frac{2}{5} =7\frac{5}{5} -3\frac{2}{5} =4\frac{3}{5} \\ \\ 9)\frac{3}{4}-\frac{3}{10} =\frac{15}{20} -\frac{6}{20}=\frac{9}{20}\\ \\ 10)\frac{5}{12}-\frac{7}{19} =\frac{95}{228} -\frac{84}{228} =\frac{11}{228} \\ \\[/tex]

[tex]11)\frac{6}{21}-\frac{3}{14} +\frac{2}{7} =\frac{12}{42}-\frac{9}{42}+\frac{12}{42} =\frac{15}{42} =\frac{5}{14} \\ \\ 12)\frac{1}{2} -(\frac{3}{5} -\frac{1}{6})=\frac{15}{30}-\frac{18}{30}+\frac{5}{30} =\frac{2}{30} =\frac{1}{15}[/tex]