There are 46 people in class 3 and 2, 18 people can only play table tennis, 7 people can play both table tennis and badminton, and 6 people can neither play table tennis nor badminton. How many people can only play badminton?
三2班有46人，仅会打乒乓球的有18人，既会打乒乓球又会打羽毛球的有7人，既不会打乒乓球又不会打羽毛球的有6人．仅会打羽毛球的有多少人？
<gadget id="calculator">46 - 6</gadget>
<output>40</output>

<gadget id="calculator">40 - 18 - 7</gadget>
<output>15</output>

<result>15</result>