rectangular piece of land with a ratio of length to width of 3:2, drawn on a scale of 1:1000, has a perimeter of 20 cm. It is planned to build a building on this land, which covers 40% of the land. What is the approximate area of the building in square meters?
一块长方形地，长和宽的比是3：2，按1：1000的比例尺画在图上，其周长是20厘米．计划在这块地上盖一幢楼，占地面积是这块地的40%，这幢楼的占地面积大约是多少平方米．
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 / 1_000</gadget>
<output>1/1_000 = around 0.001</output>

<gadget id="calculator">(3/5) / (1/1_000) / 100</gadget>
<output>6</output>

<gadget id="calculator">10 * (3/5)</gadget>
<output>6</output>

<gadget id="calculator">10 - 6</gadget>
<output>4</output>

<gadget id="calculator">4 / (1/1_000) / 100</gadget>
<output>40</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">10 * 6 * 40 * (2/5)</gadget>
<output>960</output>

<result>960</result>