A court is 30 meters long and 20 meters wide. Xiaohua walked along the court twice, how many meters did he walk in total?
一个球场长30米，宽20米，小华沿球场边走了两圈，一共走了多少米
<gadget id="calculator">30 + 20</gadget>
<output>50</output>

<gadget id="calculator">50 * 2 * 2</gadget>
<output>200</output>

<result>200</result>