There are 12 residential buildings in a community, each building has 25 floors, and each floor has 4 households. How many households are there in this community? (Step-by-step answer, and write a subtitle)
某小区有12幢居民楼，每幢有25层，每层有4户人家，这个小区共有几户人家？(分步解答，并写出小标题)
<gadget id="calculator">25 * 12</gadget>
<output>300</output>

<gadget id="calculator">4 * 300</gadget>
<output>1_200</output>

<result>1_200</result>