A rectangle has a length of 22 cm and a width of 18 cm. What is the perimeter of the rectangle in cm?
一个长方形，长是22厘米，宽是18厘米，这个长方形的周长是多少厘米．
<gadget id="calculator">22 + 18</gadget>
<output>40</output>

<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<result>80</result>