Resposta:

[tex]a)\\ \\ \frac{1}{10} +\frac{7}{10} =\frac{1+7}{10} =\frac{8}{10} =\frac{4}{5} \\ \\ \\ b)\\ \\ \frac{11}{15}+ \frac{2}{15} -\frac{4}{15} =\frac{11+2-4}{15} =\frac{9}{15} =\frac{3}{5} \\ \\ \\ c)\\ \\ \frac{13}{2} -\frac{7}{3} +\frac{1}{3} =\\ \\ mmc=6\\ \\ \frac{39-14+2}{6} =\frac{27}{6} =\frac{9}{2}\\ \\ \\ d)\\ \\ \frac{5}{18}+ \frac{4}{9}- \frac{2}{3} =\\ \\ mmc=18\\ \\ \frac{5+8-12}{18} =\frac{1}{18}[/tex]