rectangular factory is 400 meters long and 100 meters wider than it is wide. How many hectares does this factory occupy?
一个长方形的工厂，长400米，比宽多100米．这个工厂占地多少公顷？
<gadget id="calculator">400 - 100</gadget>
<output>300</output>

<gadget id="calculator">300 / 10_000</gadget>
<output>3/100 = around 0.03</output>

<gadget id="calculator">400 * (3/100)</gadget>
<output>12</output>

<result>12</result>