To expand a rectangular stadium, if the length is increased by 100 meters, the area will be increased by 2 hectares; if the width is increased by 100 meters, the area will be increased by 4 hectares, so what is the original area?
扩建一个长方形体育场，如果长增加100米，面积就增加2公顷；如果宽增加100米，面积就增加4公顷，那么它原来占地面积是多少？
<gadget id="calculator">10_000 / 100</gadget>
<output>100</output>

<gadget id="calculator">10_000 / 100 / 10_000</gadget>
<output>1/100 = around 0.01</output>

<gadget id="calculator">4 * 100 * 2 * (1/100)</gadget>
<output>8</output>

<result>8</result>