Resposta :
a)
[tex]\dfrac{2}{8}=\dfrac{2(1)}{2(4)}=\boxed{\dfrac{1}{4}}[/tex]
b)
[tex]\dfrac{30}{6}=\dfrac{6(5)}{6(1)}=\dfrac{5}{1}=\boxed{5}[/tex]
c)
[tex]\dfrac{20}{8}=\dfrac{4(5)}{4(2)}=\boxed{\dfrac{5}{2}}[/tex]
d)
[tex]\dfrac{102}{200}=\dfrac{2(51)}{2(100)}=\boxed{\dfrac{51}{100}}[/tex]
e)
[tex]\dfrac{1}{2}=\dfrac{1(1)}{1(2)}=\boxed{\dfrac{1}{2}}[/tex]