The canteen should have a glass counter with a length of 2.2 meters, a width of 40 cm, and a height of 80 cm. Now to install angle irons on all sides of the counter, at least how many meters of angle irons are needed?
小卖部要做一个长2.2米、宽40厘米、高80厘米的玻璃柜台．现在要在柜台的各边都安上角铁，至少需要多少米的角铁？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">2.2 + (2/5) + (4/5)</gadget>
<output>3.4</output>

<gadget id="calculator">3.4 * 4</gadget>
<output>13.6</output>

<result>13.6</result>