A batch of fruit came from the fruit shop. 50% of them are apples, 30% are pears, and there are 400 kg more apples than pears. How many kilograms of fruit did the fruit shop ship in total?
水果店运来一批水果．其中50%是苹果，30%是梨，并且苹果比梨多400千克．水果店一共运来多少千克水果？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(1/2) - (3/10)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">400 / (1/5)</gadget>
<output>2_000</output>

<result>2_000</result>