A rectangular piece of land has a perimeter of 40 meters and a ratio of length to width of 2:3. What is its area?
一块长方形地周长40米，长与宽的比是2：3，它的面积是多少．
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">40 / 2 / 5</gadget>
<output>4</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<gadget id="calculator">2 * 4</gadget>
<output>8</output>

<gadget id="calculator">12 * 8</gadget>
<output>96</output>

<result>96</result>