The school needs to paint the new classrooms. It is known that the length of the classroom is 9m, the width is 7.5m, the height is 3m, and the area after deducting doors and windows is 16.5m**2. If it costs 4 yuan for paint per square meter, how much will it cost to paint this classroom?
学校要粉刷新教室．已知教室的长是9m，宽是7.5m，高是3m，扣除门窗的面积16.5m**2．如果每平方米需要花4元涂料费，粉刷这个教室需要花费多少元？
<gadget id="calculator">9 * 7.5</gadget>
<output>67.5</output>

<gadget id="calculator">9 * 3</gadget>
<output>27</output>

<gadget id="calculator">7.5 * 3</gadget>
<output>22.5</output>

<gadget id="calculator">27 + 22.5</gadget>
<output>49.5</output>

<gadget id="calculator">49.5 * 2</gadget>
<output>99</output>

<gadget id="calculator">99 - 16.5</gadget>
<output>82.5</output>

<gadget id="calculator">67.5 + 82.5</gadget>
<output>150</output>

<gadget id="calculator">150 * 4</gadget>
<output>600</output>

<result>600</result>