I read a book (1/3) in the first week, and I read 50 more pages in the second week than in the first week. I just finished reading it at this time. How many pages does this book have?
一本书明明第一周看了(1/3)，第二周比第一周多看50页，这时恰好看完，这本书一共有多少页？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3) - (1/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">50 / (1/3)</gadget>
<output>150</output>

<result>150</result>