Use 72 decimeters of iron wire to form a rectangle. The ratio of the length to the width of the rectangle is 3:4. What is the area of the rectangle?
用72分米长的铁丝围成一个长方形，长方形的长和宽的比是3：4，这个长方形的面积是多少平方分米？
<gadget id="calculator">72 / 2</gadget>
<output>36</output>

<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">36 * (3/7) * 36 * (4/7)</gadget>
<output>15_552/49 = around 317.387755</output>

<result>15_552/49 = around 317.387755</result>