Xinhua Primary School has built two teaching buildings. The first building has 24 classrooms, and the second building has 18 classrooms. If each classroom needs to install 12 fluorescent lamps, how many fluorescent lamps should be installed in the two teaching buildings?
新华小学修建了两幢教学楼，第一幢有24间教室，第二幢有18间教室，如果每间教室要安装12盏日光灯，这两幢教学楼共要安装日光灯多少盏？
<gadget id="calculator">24 + 18</gadget>
<output>42</output>

<gadget id="calculator">42 * 12</gadget>
<output>504</output>

<result>504</result>