Bright Chicken Farm raised 2,400 chickens this year, an increase of (1/5) compared to last year. How many chickens were raised last year?
光明养鸡场今年养鸡2400只，比去年增加(1/5)，去年养鸡多少只？
<gadget id="calculator">1 / 5</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">2_400 / (6/5)</gadget>
<output>2_000</output>

<result>2_000</result>