The orchard harvested 4,500 kilograms of apples last year, an increase of 25% over the previous year. How many kilograms of apples were harvested in the previous year?
果园去年收苹果4500千克，比前年增25%，前年收苹果多少千克？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">4_500 / (5/4)</gadget>
<output>3_600</output>

<result>3_600</result>