The school wants to build a cuboid-shaped swimming pool, which is 50 meters long, twice the width, and 1.8 meters deep. Tiles are placed around the swimming pool and on the bottom. If 20 tiles are used per square meter, how many tiles are needed?
学校要建造一个长方体形状的游泳池，长50米，是宽的2倍，深1.8米，在游泳池的四周和底面贴瓷砖，如果每平方米用20块瓷砖，共需瓷砖多少块？
<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">50 * 25</gadget>
<output>1_250</output>

<gadget id="calculator">50 * 1.8</gadget>
<output>90</output>

<gadget id="calculator">25 * 1.8</gadget>
<output>45</output>

<gadget id="calculator">90 + 45</gadget>
<output>135</output>

<gadget id="calculator">135 * 2</gadget>
<output>270</output>

<gadget id="calculator">1_250 + 270</gadget>
<output>1_520</output>

<gadget id="calculator">1_520 * 20</gadget>
<output>30_400</output>

<result>30_400</result>