Given that (1/(x))-(1/(y))=3, then ((3x-2xy-3y)/(x+xy-y))=how much.
已知(1/(x))-(1/(y))=3，则((3x-2xy-3y)/(x+xy-y))=多少．
<gadget id="calculator">1 - 3</gadget>
<output>-2</output>

<gadget id="calculator">5 / (-2)</gadget>
<output>-5/2 = around -2.5</output>

<gadget id="calculator">3 - (-5/2)</gadget>
<output>11/2 = around 5.5</output>

<result>11/2 = around 5.5</result>