Li Qiang reads a story book. He reads 25 pages on the first day, and (1/4) of the book on the second day. There are still 50 pages left. How many pages does this book have?
李强看一本故事书，第一天看了25页，第二天看了这本书的(1/4)，还剩下50页没有看，这本书有多少页？
<gadget id="calculator">25 + 50</gadget>
<output>75</output>

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

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">75 / (3/4)</gadget>
<output>100</output>

<result>100</result>