Li Xiaohong reads an 80-page story book. She reads (1/4) of the whole book on the first day and (1/5) of the whole book on the second day. What fraction of the book is left after two days of reading?
李小红看一本80页的故事书，第一天看了全书的(1/4)，第二天看了全书的(1/5)．看两天后还剩全书的几分之几？
<gadget id="calculator">1 / 4</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>