Make a cuboid wooden box with a length of 1 meter and 2 decimeters, a width of 5 decimeters, and a height of 0.4 meters. At least how many square meters of wooden boards are needed to make this wooden box.
做一只长方体木箱，长1米2分米，宽5分米，高0.4米．做这个木箱至少要用木板多少平方米．
<gadget id="calculator">5 / 10</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1.2 * (1/2)</gadget>
<output>0.6</output>

<gadget id="calculator">1.2 * 0.4</gadget>
<output>0.48</output>

<gadget id="calculator">(1/2) * 0.4</gadget>
<output>0.2</output>

<gadget id="calculator">0.6 + 0.48 + 0.2</gadget>
<output>1.28</output>

<gadget id="calculator">1.28 * 2</gadget>
<output>2.56</output>

<result>2.56</result>