To process a cuboid tin chimney with a length of 2.5 decimeters, a width of 1.6 decimeters, and a height of 2 meters, how many square decimeters of iron sheet should be used at least?
加工一个长方体铁皮烟囱，长2.5分米，宽1.6分米，高2米，至少要用多少平方分米铁皮？
<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">2.5 * 20</gadget>
<output>50</output>

<gadget id="calculator">1.6 * 20</gadget>
<output>32</output>

<gadget id="calculator">50 + 32</gadget>
<output>82</output>

<gadget id="calculator">82 * 2</gadget>
<output>164</output>

<result>164</result>