A piece of iron wire can just form a rectangle with a length of 20 decimeters and a width of 12 decimeters. If this wire is used to form a square, what is its area?
一根铁丝正好可以围成一个长20分米，宽12分米的长方形，如果用这根铁丝围成一个正方形，它的面积有多少大？
<gadget id="calculator">20 + 12</gadget>
<output>32</output>

<gadget id="calculator">2 / 4</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">32 * (1/2)</gadget>
<output>16</output>

<gadget id="calculator">16 * 16</gadget>
<output>256</output>

<result>256</result>