Xiao Ming reads a story book. On the first day, he reads (1/4) of the whole book, and on the second day, he reads 40% of the whole book. There are 8 pages left, and there are 50 pages left. How many pages does this book have?
小明看一本故事书，第一天看了全书的(1/4)，第二天看了全书的40%少8页，还剩50页，这本书共有多少页？
<gadget id="calculator">50 - 8</gadget>
<output>42</output>

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

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (1/4) - (2/5)</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">42 / (7/20)</gadget>
<output>120</output>

<result>120</result>