A classroom needs to be paved with square bricks, and the square bricks with an area of 9 square decimeters need 480 yuan. If you use square bricks with a side length of 4 decimeters instead, how many bricks are needed?
一间教室要用方砖铺地，用面积9平方分米的方砖铺，需要480块．如果改用边长是4分米的方砖铺，需要多少块？
<gadget id="calculator">9 * 480</gadget>
<output>4_320</output>

<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<gadget id="calculator">4_320 / 16</gadget>
<output>270</output>

<result>270</result>