Teacher Wang asked two questions. Among the 12 people in the first group, 8 people got the first question right, and 10 people got the second question right. Everyone got at least one question right, and they answered both questions. How many people are there?
王老师出了两道题，在第一组的12人中，做对第一题的有8人，做对第二题的有10人，每人至少做对一题，问两题都做对的有几人？
<gadget id="calculator">10 - 12</gadget>
<output>-2</output>

<gadget id="calculator">8 + (-2)</gadget>
<output>6</output>

<result>6</result>