The canteen is going to make a glass counter with a length of 240 cm, a width of 100 cm, and a height of 80 cm. Angle irons are installed on all sides. How many meters of angle irons are needed for this counter?
小卖部要做一个长240厘米，宽100厘米，高80厘米的玻璃柜台各边都安上角铁，这个柜台需要多少米角铁？
<gadget id="calculator">240 + 80 + 100</gadget>
<output>420</output>

<gadget id="calculator">4 / 100</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">420 * (1/25)</gadget>
<output>84/5 = around 16.8</output>

<result>84/5 = around 16.8</result>