The weight of the original oranges in the fruit shop is 40% of the apples, the weight of the sold oranges is 25% of the weight of the sold apples, the weight of the remaining oranges is 50% of the remaining apples, and the remaining 900 kg of apples, how many kg of the original oranges ?
水果店原有桔子的重量是苹果的40%，卖出桔子的重量是卖出苹果的25%，剩下的桔子重量是剩下苹果的50%，苹果剩下900千克，桔子原有多少千克？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">900 * (1/2)</gadget>
<output>450</output>

<gadget id="calculator">0.25 * 900</gadget>
<output>225</output>

<gadget id="calculator">450 - 225</gadget>
<output>225</output>

<gadget id="calculator">0.4 - 0.25</gadget>
<output>0.15</output>

<gadget id="calculator">225 / 0.15</gadget>
<output>1_500</output>

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

<gadget id="calculator">1_500 * (2/5)</gadget>
<output>600</output>

<result>600</result>