The perimeter of a rectangle is 140 cm, and the ratio of length to width is 5:2. What is the area of the rectangle?
长方形的周长是140厘米，长和宽的比是5：2，这个长方形的面积是多少．
<gadget id="calculator">140 / 2</gadget>
<output>70</output>

<gadget id="calculator">5 + 2</gadget>
<output>7</output>

<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">70 * (5/7)</gadget>
<output>50</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">70 * (2/7)</gadget>
<output>20</output>

<gadget id="calculator">50 * 20</gadget>
<output>1_000</output>

<result>1_000</result>