A 60 cm long iron wire is used to form a rectangle, the ratio of length to width is 7:3, what is the area of this rectangle in square centimeters?
用一根60厘米长的铁丝围成一个长方形，长和宽的比是7：3，这个长方形的面积是多少平方厘米？
<gadget id="calculator">60 / 2</gadget>
<output>30</output>

<gadget id="calculator">7 + 3</gadget>
<output>10</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">30 * (7/10)</gadget>
<output>21</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">30 * (3/10)</gadget>
<output>9</output>

<gadget id="calculator">21 * 9</gadget>
<output>189</output>

<result>189</result>