If a house needs to be paved with square bricks, 400 square bricks with a side length of 5 decimeters are needed. If the square bricks with a side length of 4 decimeters are used instead, how many bricks are needed? (Solve with ratio)
一间房子要用方砖铺地，用边长是5分米的方砖需要400块，如果改用边长是4分米的方砖，需要多少块？(用比例解)
<gadget id="calculator">5 * 5 * 400</gadget>
<output>10_000</output>

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

<gadget id="calculator">10_000 / 16</gadget>
<output>625</output>

<result>625</result>