A truck with steel on it weighs 38 tons. After half of the steel is unloaded, the total weight of the truck is 30 tons. How many tons does this truck weigh?
一辆卡车连同上面的钢材重38吨，卸掉一半钢材后，连车共重30吨，这辆卡车有多少吨？
<gadget id="calculator">38 - 30</gadget>
<output>8</output>

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">38 - 16</gadget>
<output>22</output>

<result>22</result>