A rectangular vegetable field is 70 meters long and 50 meters wide. There is a path along the perimeter of the vegetable field. How long is the path approximately?
一块长方形菜地长70米，宽50米，沿菜地四周有一条小路，小路大约长多少
<gadget id="calculator">70 + 50</gadget>
<output>120</output>

<gadget id="calculator">120 * 2</gadget>
<output>240</output>

<result>240</result>