Đáp án:
\(A = \frac{{2507}}{{502}}.\)
Giải thích các bước giải:
\[\begin{array}{l}
A = \frac{{2005x + 2006y}}{{2005x - 2006y}}\,\\
\frac{x}{2} = \frac{y}{3} \Leftrightarrow y = \frac{3}{2}x\\
\Rightarrow A = \frac{{2005x + 2006.\frac{3}{2}x}}{{2005x - 2006.\frac{3}{2}x}} = \frac{{2005x + 3009x}}{{2005x - 3009x}} = \frac{{5014x}}{{ - 1004x}} = \frac{{2507}}{{502}}.
\end{array}\]
