The flour extraction rate of wheat is 80%. How many kilograms of wheat are needed to grind 1800 kilograms of flour in a flour mill?
小麦的出粉率是80%，面粉厂要磨出1800千克面粉，需要小麦多少千克？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1_800 / (4/5)</gadget>
<output>2_250</output>

<result>2_250</result>