There are 800 storybooks and 600 comic books, how much less comic books than storybooks.
故事书有800本，漫画书有600本，漫画书比故事书少多少．
<gadget id="calculator">800 - 600</gadget>
<output>200</output>

<gadget id="calculator">200 / 800</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>