There are three kinds of books in the school library. There are 100 known comic books, literature and art books are comic books (2/5), and comic books are science and technology books (1/4). How many books are there in total?
学校图书馆有三种书，已知连环画有100本，文艺书是连环画的(2/5)，连环画是科技书的(1/4)．三种书共有多少本？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">100 * (2/5)</gadget>
<output>40</output>

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

<gadget id="calculator">100 / (1/4)</gadget>
<output>400</output>

<gadget id="calculator">100 + 40 + 400</gadget>
<output>540</output>

<result>540</result>