To dig a canal of 1800 meters, 600 meters were dug in the first 2 days, how many days will it take to finish the rest?
挖一条1800米的水渠，前2天挖了600米，剩下的还需几天挖完？
<gadget id="calculator">1_800 - 600</gadget>
<output>1_200</output>

<gadget id="calculator">600 / 2</gadget>
<output>300</output>

<gadget id="calculator">1_200 / 300</gadget>
<output>4</output>

<result>4</result>