For a classroom, it takes 800 pieces to pave the floor with square bricks with a side length of 3 decimeters. If you use square bricks with a side length of 5 decimeters instead, how many pieces are needed? (Solve with ratio)
一间教室，用边长3分米的方砖铺地需要800块．如果改用边长5分米的方砖铺，需要多少块？(用比例解)
<gadget id="calculator">3 * 3 * 800</gadget>
<output>7_200</output>

<gadget id="calculator">5 * 5</gadget>
<output>25</output>

<gadget id="calculator">7_200 / 25</gadget>
<output>288</output>

<result>288</result>