Respuesta :
a = adult shirts sold
c = children shirts sold
we know the store sold for every 5 "a", there were 3 "c" sold, so we can say that the adult to children shirts are on a 5 : 3 ratio.
We also know that whatever "c" is, adult shirts sold last weekend was 30 more than that, or namely "c + 30".
[tex]\stackrel{\textit{\large ratios}}{\cfrac{\stackrel{adult}{a}}{\underset{children}{c}}~~ = ~~\cfrac{5}{3}}\qquad \implies \qquad \stackrel{\textit{we also know that \underline{a = c + 30}}}{\cfrac{c+30}{c}~~ = ~~\cfrac{5}{3}} \\\\\\ 3c+90=5c\implies 90 = 2c\implies \cfrac{90}{2}=c\implies \boxed{45=c}~\hfill \stackrel{c + 30}{\boxed{a=75}} \\\\[-0.35em] ~\dotfill\\\\ ~\hfill \stackrel{total~sold}{120}~\hfill[/tex]
