To make a 24-section cuboid iron chimney, each section is 2 meters long, 4 decimeters wide, and 3 decimeters high, how many square meters of iron sheet should be used at least?
做24节长方体的铁皮烟囱，每节长2米，宽4分米，高3分米，至少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">(2/5) * 2</gadget>
<output>4/5 = around 0.8</output>

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

<gadget id="calculator">(3/10) * 2</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(4/5) + (3/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">(7/5) * 2 * 24</gadget>
<output>336/5 = around 67.2</output>

<result>336/5 = around 67.2</result>