A rectangular green belt with a length of 125 meters and a width of 25 meters, how many meters should it take to walk around the green belt?
一条长方形绿化带，长是125米，宽是25米，沿着绿化带走一圈，至少多少米？
<gadget id="calculator">125 + 25</gadget>
<output>150</output>

<gadget id="calculator">150 * 2</gadget>
<output>300</output>

<result>300</result>