A rectangle is 8 meters wide and twice as long as it is wide, what is its perimeter in meters?
一个长方形，宽是8米，长是宽的2倍，它的周长是多少米．
<gadget id="calculator">8 * 2</gadget>
<output>16</output>

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

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

<result>48</result>