The teaching building of Longxin Central Primary School has 4 floors, each floor has 4 classrooms, and each classroom has 25 sets of desks and chairs. How many sets of desks and chairs does Longxin Central Primary School have?
龙新中心小学教学楼共4层，每层有4个教室，每个教室内有25套桌椅，龙新中心小学一共有多少套桌椅？
<gadget id="calculator">25 * 4</gadget>
<output>100</output>

<gadget id="calculator">100 * 4</gadget>
<output>400</output>

<result>400</result>