The fruit shop shipped 9 boxes of pears and 9 boxes of apples. The total weight of pears is 270 kg, and the total weight of apples is 180 kg. How much does each box of pears weigh more than each box of apples?
水果店运来梨和苹果各9箱，梨共重270千克，苹果共重180千克，每箱梨比每箱苹果重多少千克？
<gadget id="calculator">270 - 180</gadget>
<output>90</output>

<gadget id="calculator">90 / 9</gadget>
<output>10</output>

<result>10</result>