There are 68 people in our class, 43 people participate in the sports team, and 38 people participate in the dance team. Everyone participates in at least one team. How many people in this class participate in both teams?
我们班有68人，参加体育队的有43人，参加舞蹈队的有38人，每人至少参加一个队，那么这个班两队都参加的有多少人？
<gadget id="calculator">38 - 68</gadget>
<output>-30</output>

<gadget id="calculator">43 + (-30)</gadget>
<output>13</output>

<result>13</result>