Use a 20m long iron wire to form a rectangle, the ratio of width to length is 4:6, what is the area of this rectangle?
用一根长20m的铁丝围成一个长方形，宽与长的比是4：6，求这个长方形的面积？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">10 * (2/5)</gadget>
<output>4</output>

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

<gadget id="calculator">10 * (2/5) * 6</gadget>
<output>24</output>

<result>24</result>