rectangular playground is 25 meters long and 17 meters wide. How many meters is it to walk around the playground?
一个长方形操场长25米，宽17米，沿操场走一圈是多少米？
<gadget id="calculator">25 + 17</gadget>
<output>42</output>

<gadget id="calculator">42 * 2</gadget>
<output>84</output>

<result>84</result>