There is a classroom with a length of 9 meters, a width of 7 meters, and a height of 4 meters. The area of the doors, windows and blackboards is 32.4 square meters. To repaint the surroundings and ceiling of this classroom, how many square meters should be painted?
有一个教室长9米，宽7米，高4米，门窗黑板的面积占32.4平方米，要将这个教室的四周和顶棚重新进行粉刷，需粉刷面积是多少平方米？
<gadget id="calculator">9 * 7</gadget>
<output>63</output>

<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<gadget id="calculator">7 * 4</gadget>
<output>28</output>

<gadget id="calculator">36 + 28</gadget>
<output>64</output>

<gadget id="calculator">64 * 2</gadget>
<output>128</output>

<gadget id="calculator">128 - 32.4</gadget>
<output>95.6</output>

<gadget id="calculator">63 + 95.6</gadget>
<output>158.6</output>

<result>158.6</result>