The school wants to build a swimming pool with a length of 25 meters, a width of 10 meters, and a depth of 2 meters. Tiles are placed around and on the bottom of the swimming pool. If the tiles are squares with a side length of 2 decimeters, how many tiles are needed?
学校要修建一个长25米，宽10米，深2米的游泳池，在游泳池的四周和底部贴瓷砖，如果瓷砖是边长2分米的正方形，那么需要多少块瓷砖？
<gadget id="calculator">25 * 10</gadget>
<output>250</output>

<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<gadget id="calculator">2 * 25</gadget>
<output>50</output>

<gadget id="calculator">250 + 20 + 50</gadget>
<output>320</output>

<gadget id="calculator">320 * 2</gadget>
<output>640</output>

<gadget id="calculator">640 - 250</gadget>
<output>390</output>

<gadget id="calculator">2 / 10</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) * (1/5)</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">390 / (1/25)</gadget>
<output>9_750</output>

<result>9_750</result>