There is a batch of apples and pears in a warehouse. After 80 kg of pears are shipped out, the mass ratio of the remaining apples to pears is 5:4. If another 210 kg of apples are shipped out, the mass of the remaining apples is 20% of the pears. Then How many kilograms of pears were originally stored in the warehouse?
某仓库存有一批苹果和雪梨，运出80千克雪梨后，余下的苹果和雪梨的质量比是5：4，如果再运出210千克苹果，剩下的苹果的质量是雪梨的20%，那么仓库原来存有雪梨多少千克？
<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(5/4) - (1/5)</gadget>
<output>21/20 = around 1.05</output>

<gadget id="calculator">210 / (21/20)</gadget>
<output>200</output>

<gadget id="calculator">200 + 80</gadget>
<output>280</output>

<result>280</result>