A ventilation pipe with a length of 5 meters, a width of 4 meters and a height of 3 meters is painted on the outside. If 100 grams of paint is used per square meter, how many kilograms of paint are needed to make this ventilation pipe?
一节长5米，宽4米，高3米的通风管，把它外面涂上油漆，如果每平方米用油漆100克，制作这个通风管至少需要油漆多少千克？
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">15 + 20</gadget>
<output>35</output>

<gadget id="calculator">100 / 1_000</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">35 * 2 * (1/10)</gadget>
<output>7</output>

<result>7</result>