24 teachers from the school took students from 12 classes to participate in the "Science and Technology Exhibition", with an average of 45 students in each class. How many people from the school participated in this activity?
学校24位老师带着12个班的同学参加"科技展览"活动，平均每个班45人．学校一共有多少人参加这次活动？
<gadget id="calculator">45 * 12</gadget>
<output>540</output>

<gadget id="calculator">540 + 24</gadget>
<output>564</output>

<result>564</result>