There are 12 people in the math group and 25 people in the music group, and 8 of them participate in both the math group and the music group. How many people are there in the two groups?
数学小组有12人，音乐小组25人，其中有8人既参加数学小组又参加音乐小组，这两个小组一共多少人．
<gadget id="calculator">25 - 8</gadget>
<output>17</output>

<gadget id="calculator">12 + 17</gadget>
<output>29</output>

<result>29</result>