A rectangular playground is 50 meters long and 10 meters wide. How many meters does it take to run around the playground?
一个长方形操场，长50米，宽10米，沿操场跑1圈，要跑多少米？
<gadget id="calculator">50 + 10</gadget>
<output>60</output>

<gadget id="calculator">60 * 2</gadget>
<output>120</output>

<result>120</result>