55% of the total length of a canal has been repaired, and how much remains to be repaired.
一条水渠，已修了全长的55%，还剩多少没有修．
<gadget id="calculator">55 / 100</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">1 - (11/20)</gadget>
<output>9/20 = around 0.45</output>

<result>9/20 = around 0.45</result>