Xiao Ming reads a 600-page story book, and has already read 320 pages. The rest plans to read 35 pages a day. How many days will it take to finish reading?
小明读一本600页的故事书，已经读了320页，剩下的计划每天读35页，还需几天读完？
<gadget id="calculator">600 - 320</gadget>
<output>280</output>

<gadget id="calculator">280 / 35</gadget>
<output>8</output>

<result>8</result>