A piece of iron wire can just form a square with a side length of 12 cm. If it is surrounded by a rectangle with a length of 16 cm, what is the width in cm?
一根铁丝正好可以围成边长是12厘米的正方形，如果把它围成长是16厘米的长方形，宽应是多少厘米．
<gadget id="calculator">12 * 4</gadget>
<output>48</output>

<gadget id="calculator">48 / 2</gadget>
<output>24</output>

<gadget id="calculator">24 - 16</gadget>
<output>8</output>

<result>8</result>