Science and technology books in the school library account for 50% of the total number of books, and story books account for 40% of the total number of books. There are 1,600 more science and technology books than story books. How many books are there in the school library?
学校图书馆科技书占图书总数的50%，故事书占图书总数的40%，科技书比故事书多1600本．学校图书馆共有图书多少本？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

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

<gadget id="calculator">(1/2) - (2/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1_600 / (1/10)</gadget>
<output>16_000</output>

<result>16_000</result>