A swimming pool is 25m long, 10m wide, and 1.6m deep. Tiles are laid around the swimming pool and at the bottom of the pool. If the side length of the tiles is a square of 5dm, how many pieces of this kind of tiles are needed at least?
一个游泳池长是25m，宽是10m，深是1.6m，在游泳池的四周和池底砌瓷砖，如果瓷砖的边长是5dm的正方形，那么至少需要这种瓷砖多少块？
<gadget id="calculator">25 * 10</gadget>
<output>250</output>

<gadget id="calculator">25 * 1.6</gadget>
<output>40</output>

<gadget id="calculator">10 * 1.6</gadget>
<output>16</output>

<gadget id="calculator">250 + 40 + 16</gadget>
<output>306</output>

<gadget id="calculator">306 * 2</gadget>
<output>612</output>

<gadget id="calculator">612 - 250</gadget>
<output>362</output>

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

<gadget id="calculator">362 / 0.25</gadget>
<output>1_448</output>

<result>1_448</result>