Read a storybook, read 25% of the book on the first day, and read 50 pages on the second day, just read (3/4) of the book in two days, how many pages of this storybook?
读一本故事书，第一天读了这本书的25%，第二天又读了50页，两天刚好读这本书的(3/4)，这本故事书多少页？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(3/4) - (1/4)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">50 / (1/2)</gadget>
<output>100</output>

<result>100</result>