A rectangular flower bed is 18 meters long and twice as wide. What is the perimeter of the flower bed?
一个长方形的花坛，长是18米，是宽的2倍，这个花坛的周长是多少？
<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">18 + 9</gadget>
<output>27</output>

<gadget id="calculator">27 * 2</gadget>
<output>54</output>

<result>54</result>