A total of 34 students are competing on 12 table tennis tables. How many table tennis tables are playing doubles?
12张乒乓球桌上一共有34个同学在比赛，正在双打的乒乓球桌有多少张．
<gadget id="calculator">34 - 24</gadget>
<output>10</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<result>5</result>