100 kg of peanuts can extract 40 kg of oil, so how many kg of peanuts are needed to extract 20 kg of oil?
100千克花生可榨油40千克，则榨油20千克需要花生多少千克．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 / (2/5)</gadget>
<output>50</output>

<result>50</result>