For a novel, Xiao Ming read 1/3 of the whole book on the first day, 25% of the whole book on the second day, and left the rest of the book unread.
一本小说，小明第一天看了全书的(1/3)，第二天看了全书的25%，还剩下全书的多少没有看．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/3) - (1/4)</gadget>
<output>5/12 = around 0.416667</output>

<result>5/12 = around 0.416667</result>