Resposta :
D)
[tex]\frac{5}{25}+\frac{2}{6}-\frac{2}{8}\\\\\frac{1}{5}+\frac{2}{6}-\frac{2}{8}\\\\\frac{1}{5}+\frac{1}{3}-\frac{2}{8}\\\\\frac{1}{5}+\frac{1}{3}-\frac{1}{4}\\\\\frac{12}{60}+\frac{20}{60}-\frac{15}{60}\\\\\mathrm{Aplicar\:as\:propriedades\:das\:fracos}:\quad \frac{a}{c}\pm \frac{b}{c}=\frac{a\pm \:b}{c}\\\\\frac{12+20-15}{60}\\\\12+20-15=17\\\\\frac{17}{60}[/tex]
E)
[tex]\frac{2}{4}\times \frac{4}{6}\div \frac{5}{10}\\\\\frac{2}{4}\times \frac{4}{6}\times \frac{10}{5}\\\\\frac{2\times \:4\times \:10}{4\times \:6\times \:5}\\\\\frac{2\times \:10}{6\times \:5}\\\\\frac{20}{6\times \:5}\\\\\frac{20}{30}\\\\\frac{2}{3}[/tex]