Xiaoli reads a book. She reads 28 pages on the first day and 22 pages on the second day. There are still (3/4) of this book left unread. How many pages does this book have?
小丽看一本书，第一天看了28页，第二天看了22页，还剩下这本书的(3/4)没读，这本书有多少页？
<gadget id="calculator">28 + 22</gadget>
<output>50</output>

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

<gadget id="calculator">1 - (3/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">50 / (1/4)</gadget>
<output>200</output>

<result>200</result>