Xiao Ming reads a book. It is known that the number of pages he has read is 2 pages more than 20% of the whole book, and the number of pages he has not read is 10 pages more than 75% of the whole book. How many pages does this book have?
小明读一本书，已知他已读的页数比全书的20%多2页，没读的页数比全书的75%多10页，这本书共有多少页？
<gadget id="calculator">2 + 10</gadget>
<output>12</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">75 / 100</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (1/5) - (3/4)</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">12 / (1/20)</gadget>
<output>240</output>

<result>240</result>