A book has 100 pages, and 28 pages have been read, what percentage is left?
一本书100页，已经看了28页，还剩下百分之几没有看？
<gadget id="calculator">100 - 28</gadget>
<output>72</output>

<gadget id="calculator">72 / 100</gadget>
<output>18/25 = around 0.72</output>

<result>18/25 = around 0.72</result>