\[\boxed{\mathbf{335}.}\]
\[ax^{2} + bx + c = 0\]
\[x^{2} + \frac{b}{a}x + \frac{c}{a} = 0\]
\[По\ теореме\ Виета:\]
\[x_{1} + x_{2} = - \frac{b}{a};\ \ \ x_{1} \cdot x_{2} = \frac{c}{a}.\]
\[x^{2} + px + q = 0\]
\[y_{1} = \frac{1}{x_{1}};\ \ \ y_{2} = \frac{1}{x_{2}};\]
\[- p = \frac{1}{x_{1}} + \frac{1}{x_{2}} = \frac{x_{1} + x_{2}}{x_{1} \cdot x_{2}} =\]
\[= - \frac{b}{a}\ :\frac{c}{a} = - \frac{b}{a} \cdot \frac{a}{c} = - \frac{b}{c};\]
\[q = \frac{1}{x_{1}} \cdot \frac{1}{x_{2}} = 1\ :\frac{c}{a} = \frac{a}{c}.\]
\[Получаем\ уравнение:\]
\[x^{2} + \frac{b}{c}x + \frac{a}{c} = 0\ \ \ \ | \cdot c\]
\[cx^{2} + bx + a = 0.\]