A computer classroom needs 400 yuan to pave the floor with square bricks with a side length of 3 decimeters. If the floor is paved with square bricks with a side length of 4 decimeters, how many bricks are needed? 【Answer with proportion】.
一间电脑教室，用边长3分米的方砖铺地，需要400块．如果改用边长是4分米的方砖铺地，需要多少块？【用比例解答】．
<gadget id="calculator">3 * 3 * 400</gadget>
<output>3_600</output>

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

<gadget id="calculator">3_600 / 16</gadget>
<output>225</output>

<result>225</result>