Zhang Hua reads a copy of "Youth Literature and Art". I read 50 pages on the first day, and (1/4) of the whole book on the second day, leaving 25 pages unread. How many pages does this book have?
张华看一本《少年文艺》．第一天看了50页，第二天看了全书的(1/4)，还剩25页没看．这本书一共有多少页？
<gadget id="calculator">50 + 25</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>