If the length of a rectangle is 6 cm and the width is half the length, what is its perimeter in cm
一个长方形的长是6厘米，宽是长的一半，它的周长是多少厘米
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">6 + 3</gadget>
<output>9</output>

<gadget id="calculator">9 * 2</gadget>
<output>18</output>

<result>18</result>