If a classroom is paved with square bricks with a side length of 0.4 meters, 300 pieces are needed. If the floor is paved with square bricks with a side length of 0.5 meters, how many pieces are needed?
一间教室用边长0.4米的正方形砖铺地，需要300块，如果改用边长0.5米的正方形砖铺地，需要多少块？
<gadget id="calculator">0.4 * 0.4 * 300</gadget>
<output>48</output>

<gadget id="calculator">0.5 * 0.5</gadget>
<output>0.25</output>

<gadget id="calculator">48 / 0.25</gadget>
<output>192</output>

<result>192</result>