To lay square bricks on the floor of a room, 720 square bricks with an area of 4 square decimeters are used to cover it exactly. If square bricks with a side length of 3 decimeters are used, how many square bricks are needed to cover the room?
在一个房间地面上铺方砖，用面积4平方分米的方砖，720块正好铺满，如果用边长3分米的方砖，需多少块铺满这个房间？
<gadget id="calculator">4 * 720</gadget>
<output>2_880</output>

<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<gadget id="calculator">2_880 / 9</gadget>
<output>320</output>

<result>320</result>