a) [tex]\frac{\frac{1}{3}+\frac{5}{7}}{2}=\frac{\frac{22}{21}}{2}=\frac{22}{21\cdot \:2}=\frac{22}{42}=\frac{11}{21}[/tex]
b) [tex]\frac{\frac{3}{4}+\frac{5}{6}+\frac{2}{7}}{3}=\frac{\frac{157}{84}}{3}=\frac{157}{84\cdot \:3}=\frac{157}{252}[/tex]
c)[tex]\frac{\frac{1}{2}-\frac{1}{2}+4-4}{4}=\frac{0}{4}=\frac{0}{4}[/tex]
d) [tex]\frac{-\frac{3}{5}+0.2-0.8}{4}=\frac{-\frac{3}{5}-0.6}{4}=\frac{-0.6-0.6}{4}=-\frac{1.2}{4}=-0.3[/tex]
6) [tex]\frac{\frac{1}{2}+x}{2}=\frac{1}{5}[/tex]
[tex]\frac{1}{2}+x=\frac{2}{5}[/tex]
[tex]x=\frac{2}{5}-\frac{1}{2}[/tex]
[tex]x=-\frac{1}{10}[/tex]
