The ratio of length to width of a rectangle is 7:5. If the length is reduced by 1/5 and the width is increased by 12cm, it becomes a square. What is the area of the original rectangle in cm**2.
一个长方形的长宽之比是7：5，如果把长减少(1/5)，宽增加12cm，它就变一个正方形，原长方形的面积是多少cm**2．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">7 * (1/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">7 - 5 - (7/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">12 / (3/5)</gadget>
<output>20</output>

<gadget id="calculator">7 * 20 * 5 * 20</gadget>
<output>14_000</output>

<result>14_000</result>