A story book has 100 pages in total. Xiaohong reads 25 pages on the first day and 1/5 of the whole book on the second day. What percentage of the book is left?
一本故事书共100页，小红第一天看了25页，第二天看了全书的(1/5)，全书还剩下几分之几没有看？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/4) - (1/5)</gadget>
<output>11/20 = around 0.55</output>

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