A classroom is 8 meters long, 7 meters wide, and 3 meters high. The doors, windows, and blackboards of the classroom have a total area of 30 square meters. To paint the top surface and surrounding walls of the classroom, how many square meters is the painted area?
一间教室长8米、宽7米、高3米，教室的门窗、黑板面积共30平方米．要粉刷教室的顶面和四周墙壁，粉刷的面积有多少平方米？
<gadget id="calculator">8 * 3</gadget>
<output>24</output>

<gadget id="calculator">7 * 3</gadget>
<output>21</output>

<gadget id="calculator">24 + 21</gadget>
<output>45</output>

<gadget id="calculator">45 * 2</gadget>
<output>90</output>

<gadget id="calculator">8 * 7</gadget>
<output>56</output>

<gadget id="calculator">56 - 30</gadget>
<output>26</output>

<gadget id="calculator">90 + 26</gadget>
<output>116</output>

<result>116</result>