Respuesta :

[tex]\bf 80~~,~~20~~,~~5~\hfill \cfrac{20}{80}\implies \boxed{\cfrac{1}{4}}~~,~~ \cfrac{5}{20}\implies \boxed{\cfrac{1}{4}}~\hfill \stackrel{\textit{common ratio}}{\boxed{\cfrac{1}{4}}}[/tex]