The corn production in Longchang Township this year has increased by 20% compared to last year. This year's corn production is 8,400 tons. So how many tons was the production last year?
龙场乡今年的玉米产量比去年增加20%，今年的玉米产量是8400吨，那么去年的产量是多少吨？
<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">8_400 / (6/5)</gadget>
<output>7_000</output>

<result>7_000</result>