The perimeter of a rectangular vegetable field is 720 meters, and the ratio of length to width is 5:7. What is the area of this vegetable field?
一块长方形菜地的周长是720米，长与宽的比是5：7．这块菜地的面积是多少？
<gadget id="calculator">720 / 2</gadget>
<output>360</output>

<gadget id="calculator">5 + 7</gadget>
<output>12</output>

<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">360 * (5/12)</gadget>
<output>150</output>

<gadget id="calculator">7 / 12</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">360 * (7/12)</gadget>
<output>210</output>

<gadget id="calculator">150 * 210</gadget>
<output>31_500</output>

<result>31_500</result>