A batch of food can feed 25 children for 20 days; after 8 days, the number of children increased by 5, how many more days can we support?
粮食一批，可供25名院童20日食用；8天后，院童人数多了5人，问还可支持多少天？
<gadget id="calculator">25 * 20</gadget>
<output>500</output>

<gadget id="calculator">1 / 500</gadget>
<output>1/500 = around 0.002</output>

<gadget id="calculator">(1/500) * 8 * 25</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">25 + 5</gadget>
<output>30</output>

<gadget id="calculator">(1/500) * 30</gadget>
<output>3/50 = around 0.06</output>

<gadget id="calculator">(3/5) / (3/50)</gadget>
<output>10</output>

<result>10</result>