A story book, Xiaowen has already read (3/5) of the whole book, and the rest of the book has not been read.
一本故事书，小文已经看了全书的(3/5)，还剩下全书的多少没有看．
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>