There are 800 kilograms more pears than apples in the fruit market. After selling 1000 kilograms of each of the two kinds of fruits, the weight of the remaining pears is exactly three times that of the remaining apples. How many kilograms of apples are there in the fruit market?
水果商场原有梨比苹果多800千克，两种水果各卖出1000千克后，剩下的梨的重量恰好是剩下苹果的3倍．水果商场原有苹果多少千克．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">800 / 2</gadget>
<output>400</output>

<gadget id="calculator">400 + 1_000</gadget>
<output>1_400</output>

<result>1_400</result>