When Xiaohong reads a book, she has already read 40%, and the remaining pages are 24 more than what she has read. How many pages are there in this book?
小红看一本书，已经看了40%，剩下的比已看的多24页，这本书有多少页．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">24 / (1/5)</gadget>
<output>120</output>

<result>120</result>