There are 12 students in a certain group. The head teacher wants to play a game with any two of them. How many games will the head teacher play in total?
某小组有12名学生，班主任要与其中任意两名学生一起做一次游戏，问班主任一共要做多少次游戏？
<gadget id="calculator">12 * 11</gadget>
<output>132</output>

<gadget id="calculator">2 * 1</gadget>
<output>2</output>

<gadget id="calculator">132 / 2</gadget>
<output>66</output>

<gadget id="calculator">1 * 66</gadget>
<output>66</output>

<result>66</result>