A batch of tomatoes was shipped from the vegetable market, 40% of the total was sold on the first day, 1200 kilograms were sold on the second day, and 600 kilograms remained. How many kilograms are there in total for this batch of tomatoes?
菜市场运来一批西红柿，第一天卖出了总数的40%，第二天卖了1200千克，还剩600千克．这批西红柿共有多少千克？
<gadget id="calculator">1_200 + 600</gadget>
<output>1_800</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1_800 / (3/5)</gadget>
<output>3_000</output>

<result>3_000</result>