A box of apples weighs 30 kilograms. After eating half of them, the box still weighs 16 kilograms. Children: Please calculate how much this box weighs?
一箱苹果连箱共重30千克，吃了一半后，连箱还重16千克，小朋友：请你算一算这个箱重多少？
<gadget id="calculator">30 - 16</gadget>
<output>14</output>

<gadget id="calculator">14 * 2</gadget>
<output>28</output>

<gadget id="calculator">30 - 28</gadget>
<output>2</output>

<result>2</result>