The width of a rectangle is 10 cm. After reducing the length by 20%, it becomes a square. What is the area of the original rectangle?
一个长方形的宽是10厘米，把长减少20%以后，它就变成了正方形，原来长方形的面积是多少？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">10 / (4/5)</gadget>
<output>25/2 = around 12.5</output>

<gadget id="calculator">(25/2) * 10</gadget>
<output>125</output>

<result>125</result>