Class five (four) needs to make a cuboid trash can without a cover. It is 50cm long, 30cm wide, and 6.8dm high. How many square decimeters of iron sheet are needed to make this trash can?
五(四)班要制作一个无盖的长方体垃圾桶，它的长50cm，宽30cm，高6.8dm，做这个垃圾桶至少需要多少平方分米的铁皮？
<gadget id="calculator">50 * 30</gadget>
<output>1_500</output>

<gadget id="calculator">50 * 6.8 * 10</gadget>
<output>3_400</output>

<gadget id="calculator">30 * 6.8 * 10</gadget>
<output>2_040</output>

<gadget id="calculator">3_400 + 2_040</gadget>
<output>5_440</output>

<gadget id="calculator">5_440 * 2</gadget>
<output>10_880</output>

<gadget id="calculator">1_500 + 10_880</gadget>
<output>12_380</output>

<gadget id="calculator">12_380 / 100</gadget>
<output>619/5 = around 123.8</output>

<result>619/5 = around 123.8</result>