There are 48 students, 10 of them can play the piano, 30 can play the clarinet, 16 can neither, how many can play both?
有48名学生，其中会弹钢琴的有10人，会吹竖笛的有30人，两样都不会的有16人，两样都会的有多少人？
<gadget id="calculator">48 - 16</gadget>
<output>32</output>

<gadget id="calculator">30 - 32</gadget>
<output>-2</output>

<gadget id="calculator">10 + (-2)</gadget>
<output>8</output>

<result>8</result>