The students participated in the "Patriot" summer camp by boat. They all lived on the second and third floors of the fourth-class cabin. There were 15 rooms on the second floor and 8 rooms on the third floor. Each room accommodated 6 people. How many people attend this event?
同学们乘船参加"爱国者"夏令营活动，他们都住在四等舱的二楼和三楼，二楼住了15个房间，三楼住了8个房间，每间住6人，一共有多少人参加这次活动？
<gadget id="calculator">15 + 8</gadget>
<output>23</output>

<gadget id="calculator">23 * 6</gadget>
<output>138</output>

<result>138</result>