How many square decimeters of iron sheet should be used to process a cuboid iron chimney with a length of 2.5cm, a width of 1.6cm, and a height of 2cm?
加工一个长方体铁皮烟囱，长2.5cm，宽1.6cm，高2cm至少要用多少平方分米铁皮？
<gadget id="calculator">2.5 * 2</gadget>
<output>5</output>

<gadget id="calculator">1.6 * 2</gadget>
<output>3.2</output>

<gadget id="calculator">5 + 3.2</gadget>
<output>8.2</output>

<gadget id="calculator">2 / 100</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">8.2 * (1/50)</gadget>
<output>0.164</output>

<result>0.164</result>