Xiaohua reads a book. He reads 50% of the book on the first day, and 1/4 of the book on the second day. There are 60 pages left. How many pages does this book have?
小华看一本书，第一天看了全书的50%，第二天看了全书的(1/4)，还剩60页没有看，这本书共有多少页？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/2) - (1/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">60 / (1/4)</gadget>
<output>240</output>

<result>240</result>