The number of scientific and technological books in the reading room is equivalent to (5/8) of literary books, and the literary and artistic books are equivalent to (2/11) of all books. Among them, there are 250 scientific and technological books. How many books are there in the reading room?
阅览室里科技书的本数相当于文艺书的(5/8)，文艺书相当于全部书的(2/11)，其中科技书有250本，阅览室里共有多少本书？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">250 / (5/8)</gadget>
<output>400</output>

<gadget id="calculator">2 / 11</gadget>
<output>2/11 = around 0.181818</output>

<gadget id="calculator">400 / (2/11)</gadget>
<output>2_200</output>

<result>2_200</result>