Pave the floor for a conference room. Originally planned to use square bricks with a side length of 4 decimeters, 900 pieces are needed; how many pieces are actually needed to use square bricks with a side length of 6 decimeters? (Solve with ratio)
给一间会议室铺地．原计划用边长4分米的方砖，需要900块；实际改用边长6分米的方砖，需要多少块？(用比例解)
<gadget id="calculator">900 * 4 * 4</gadget>
<output>14_400</output>

<gadget id="calculator">6 * 6</gadget>
<output>36</output>

<gadget id="calculator">14_400 / 36</gadget>
<output>400</output>

<result>400</result>