If (2011/2012)*2013=(2011/2012)+x is established, then x=how much.
如果(2011/2012)*2013=(2011/2012)+x成立，则x=多少．
<gadget id="calculator">2_011 / 2_012</gadget>
<output>2_011/2_012 = around 0.999503</output>

<gadget id="calculator">(2_011/2_012) * 2_013</gadget>
<output>4_048_143/2_012 = around 2_011.999503</output>

<gadget id="calculator">(4_048_143/2_012) - (2_011/2_012)</gadget>
<output>2_011</output>

<result>2_011</result>