The length of a classroom is 8 meters, the width is 6 meters, and the height is 3.5 meters. The area of doors and windows is 21.5 square meters. If the walls and roof of the classroom are to be painted, how many square meters is the area to be painted?
一间教室的长是8米，宽是6米，高是3.5米，门窗的面积是21.5平方米，要粉刷教室的四壁和屋顶，求粉刷的面积是多少平方米？
<gadget id="calculator">8 * 6</gadget>
<output>48</output>

<gadget id="calculator">8 * 3.5</gadget>
<output>28</output>

<gadget id="calculator">6 * 3.5</gadget>
<output>21</output>

<gadget id="calculator">28 + 21</gadget>
<output>49</output>

<gadget id="calculator">49 * 2</gadget>
<output>98</output>

<gadget id="calculator">98 - 21.5</gadget>
<output>76.5</output>

<gadget id="calculator">48 + 76.5</gadget>
<output>124.5</output>

<result>124.5</result>