There are 80 students in a certain school who are music or sports lovers, 36 of them are music lovers, 55 are sports lovers, how many people like both?
某校有80名同学是音乐或体育爱好者，其中有36人爱好音乐，55人爱好体育，两项都爱好的有几人？
<gadget id="calculator">55 - 80</gadget>
<output>-25</output>

<gadget id="calculator">36 + (-25)</gadget>
<output>11</output>

<result>11</result>