let's say those numbers are "a" and "b"
so.. we know that a/b are 7/5, whatever "a" and "b" may be
and we also know that their sum is 36, or a + b = 36
thus [tex]\bf \begin{cases}
\cfrac{a}{b}=\cfrac{7}{5}\implies \boxed{a}=\cfrac{7b}{5}\\\\
a+b=36\\
----------\\
\boxed{\cfrac{7b}{5}}+b=36
\end{cases}[/tex]
solve for "b", to see what "b" is
what's "a"? well [tex]\bf a=\cfrac{7b}{5}[/tex]