\[\boxed{\text{225\ (225).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\frac{x + y}{y} = 3\]
\[x + y = 3y\]
\[x = 2y\]
\[\textbf{а)}\ \frac{x}{y} = \frac{2y}{y} = 2\]
\[\textbf{б)}\ \frac{y}{x + y} = \frac{y}{2y + y} = \frac{y}{3y} = \frac{1}{3}\ \]
\[\textbf{в)}\ \frac{x - y}{y} = \frac{2y - y}{y} = \frac{y}{y} = 1\]
\[\textbf{г)}\ \frac{y}{x} = \frac{y}{2y} = \frac{1}{2}\]