The perimeter of a rectangular test field is 120 meters. It is known that the ratio of length to width is 2:1. What is the area of this test field in square meters?
一块长方形试验田的周长是120米，已知长与宽的比是2：1，这块试验田的面积是多少平方米？
<gadget id="calculator">120 / 2</gadget>
<output>60</output>

<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">60 * (1/3)</gadget>
<output>20</output>

<gadget id="calculator">60 - 20</gadget>
<output>40</output>

<gadget id="calculator">40 * 20</gadget>
<output>800</output>

<result>800</result>