To make an 8-section cuboid iron chimney, each section is 0.9 meters long, 4 decimeters wide, and 30 centimeters high, how many square meters of iron sheets should be used at least?
要制作8节长方体的铁皮烟囱，每节长0.9米，宽4分米，高30厘米，至少要用多少平方米的铁皮？
<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">0.9 * (2/5)</gadget>
<output>0.36</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">0.9 * (3/10)</gadget>
<output>0.27</output>

<gadget id="calculator">0.36 + 0.27</gadget>
<output>0.63</output>

<gadget id="calculator">0.63 * 2 * 8</gadget>
<output>10.08</output>

<result>10.08</result>