There are 7 students in the classroom, with an average age of 10 years old, and a teacher came. At this time, the average age of 8 students is 12 years old. How old is the teacher?
教室里有7名学生，平均年龄10岁，来了一位老师，这时8人的年均年龄为12岁．老师的年龄是多少岁．
<gadget id="calculator">12 * 8</gadget>
<output>96</output>

<gadget id="calculator">10 * 7</gadget>
<output>70</output>

<gadget id="calculator">96 - 70</gadget>
<output>26</output>

<result>26</result>