A conference room needs floor tiles. If you use square bricks with a side length of 3 decimeters, you need 800 pieces; if you use square bricks with an area of 25 square decimeters, how many pieces are needed at least?
一间会议室要铺地砖．如果用边长3分米的方砖铺，需要800块；如果改用面积是25平方分米的方砖铺，至少需要多少块？
<gadget id="calculator">3 * 3 * 800</gadget>
<output>7_200</output>

<gadget id="calculator">7_200 / 25</gadget>
<output>288</output>

<result>288</result>