If you stack up 8 identical exercise books, the height is 40 mm. If you stack up 56 such books, how many mm is the height?
把8本同样的练习本摞起来，高40毫米，如果把56本这样的本子摞起来，高多少毫米．
<gadget id="calculator">40 / 8</gadget>
<output>5</output>

<gadget id="calculator">5 * 56</gadget>
<output>280</output>

<result>280</result>