A classroom with a length of 10 meters, a width of 6 meters, and a height of 4 meters has an area of 9.5 square meters for doors, windows and blackboards. Now it is necessary to paint the ceiling and four walls of the classroom. If the painting costs 0.8 yuan per square meter, how much will it cost? Yuan?
一间长10米，宽6米，高4米的教室，门窗和黑板的面积是9.5平方米，现在要粉刷教室的天花板和四面墙壁，如果粉刷每平方米需0.8元，共要花去多少元？
<gadget id="calculator">10 * 6</gadget>
<output>60</output>

<gadget id="calculator">10 * 4 * 2</gadget>
<output>80</output>

<gadget id="calculator">6 * 4 * 2</gadget>
<output>48</output>

<gadget id="calculator">48 - 9.5</gadget>
<output>38.5</output>

<gadget id="calculator">60 + 80 + 38.5</gadget>
<output>178.5</output>

<gadget id="calculator">178.5 * 0.8</gadget>
<output>142.8</output>

<result>142.8</result>