The perimeter of a rectangle is 420 cm, and the ratio of length to width is 4:3. What is the area of the rectangle?
长方形的周长为420厘米，长和宽的比是4：3，这个长方形的面积是多少平方分米？
<gadget id="calculator">420 / 2</gadget>
<output>210</output>

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

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

<gadget id="calculator">(3/7) / 100</gadget>
<output>3/700 = around 0.004286</output>

<gadget id="calculator">120 * 210 * (3/700)</gadget>
<output>108</output>

<result>108</result>