45% of a piece of land has been plowed, and how much is left unplowed.
一块地已耕45%，还剩多少没有耕．
<gadget id="calculator">45 / 100</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">1 - (9/20)</gadget>
<output>11/20 = around 0.55</output>

<result>11/20 = around 0.55</result>