[tex]x;y\in\mathbb{R^+}-two\ positive\ numbers\ (x \ \textgreater \ 0\ and\ y \ \textgreater \ 0)\\x \ \textgreater \ y\\\\x+y=55(x-y)\\\\x+y=55x-55y\ \ \ \ |subtract\ "y"\ from\ both\ sides\\\\x=55x-56y\ \ \ \ |subtract\ 55x\ from\ both\ sides\\\\-54x=-56y\ \ \ |divide\ both\ sides\ by\ (-54)\\\\x=\dfrac{-56y}{-54}\\\\x=\dfrac{28}{27}y\ \ \ \ |divide\ both\ sides\ by\ "y"\\\\\boxed{\dfrac{x}{y}=\dfrac{28}{27}}\to\boxed{x:y=28:27}[/tex]