Honghong reads an extra-curricular book, and reads (1/5) of the whole book on the first day. If she reads another 24 pages, she just finishes half of the book. How many pages does this extra-curricular book have?
红红读一本课外书，第一天读了全书的(1/5)，如果再读24页，恰好读完这本书的一半，这本课外书共有多少页？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

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

<gadget id="calculator">1 - (1/2) - (1/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">24 / (3/10)</gadget>
<output>80</output>

<result>80</result>