Respuesta :

[tex]\begin{array}{ccll} \stackrel{guys}{good}&\stackrel{guys}{bad}\\ \cline{1-2} 15&4\\ 75&x \end{array}\implies \cfrac{15}{75}=\cfrac{4}{x}\implies \cfrac{1}{5}=\cfrac{4}{x}\implies x = 20[/tex]