Paint a rectangular classroom with a length of 10 meters, a width of 8 meters, and a height of 3.8 meters. Excluding the door and window area of 38 square meters, it is known that 0.4 kilograms of paint is used per square meter. How many kilograms of paint will be used in this classroom?
粉刷一间长10米、宽8米，高3.8米的长方形教室，除去门窗面积38平方米，已知每平方米用涂料0.4千克，这间教室一共要用多少千克涂料？
<gadget id="calculator">10 * 8</gadget>
<output>80</output>

<gadget id="calculator">10 * 3.8 * 2</gadget>
<output>76</output>

<gadget id="calculator">8 * 3.8 * 2</gadget>
<output>60.8</output>

<gadget id="calculator">60.8 - 38</gadget>
<output>22.8</output>

<gadget id="calculator">80 + 76 + 22.8</gadget>
<output>178.8</output>

<gadget id="calculator">178.8 * 0.4</gadget>
<output>71.52</output>

<result>71.52</result>