The printing factory is binding 910 books, an average of 90 books are bound every day. After working for many days, there are still 190 books left unfinished.
印刷厂在装订910本图书，平均每天装订90本，工作多少天后，还剩下190本没完成．
<gadget id="calculator">910 - 190</gadget>
<output>720</output>

<gadget id="calculator">720 / 90</gadget>
<output>8</output>

<result>8</result>