A new swimming pool is built in the garden expo garden. The length of the swimming pool is 50m, twice the width, and the depth is 2.8m. Now the swimming pool is covered with tiles around and on the bottom. How many square meters of tiles are needed?
园博园里新建一个游泳池，该游泳池的长50m，是宽的2倍，深2.8m．现在游泳池的四周和底面都贴上瓷砖，共需贴多少平方米的瓷砖？
<gadget id="calculator">50 / 2</gadget>
<output>25</output>

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

<gadget id="calculator">50 * 2.8 * 2</gadget>
<output>280</output>

<gadget id="calculator">25 * 2.8 * 2</gadget>
<output>140</output>

<gadget id="calculator">1_250 + 280 + 140</gadget>
<output>1_670</output>

<result>1_670</result>