There are 5 boxes of fruit in the store. After removing 6 kg from each box, the remaining fruit is exactly the mass of the original 3 boxes of fruit. What is the original weight of each box of fruit?
商店有5箱水果，从每箱取出6千克后，余下的水果恰好是原来3箱水果的质量，原来每箱水果重多少千克．
<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>