There are 400 story books in the school library, the comic books are story books (5/8), and the science and technology books are comic books (7/10). How many science and technology books are there in the school library?
学校图书室有故事书400本，连环画是故事书的(5/8)，科技书是连环画的(7/10)．学校图书室科技书有多少本？
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">400 * (5/8) * (7/10)</gadget>
<output>175</output>

<result>175</result>