Tongji Township produces 600 kilograms of wheat per mu this year, 20% more than last year. How many kilograms of wheat was produced per mu last year?
通济乡今年每亩产小麦600千克，比去年每亩增产20%．去年每亩产小麦多少千克？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">600 / (6/5)</gadget>
<output>500</output>

<result>500</result>