A room is 6 meters long, 3.5 meters wide, and 3 meters high, and the area of doors and windows is 10 square meters. Now to paste wallpaper on the four walls of this room, at least how many square meters of wallpaper is needed?
一个房间长6米、宽3.5米、高3米，门窗面积是10平方米．现在要在给这个房间的四壁贴墙纸，至少需要墙纸多少平方米？
<gadget id="calculator">6 * 3</gadget>
<output>18</output>

<gadget id="calculator">3 * 3.5</gadget>
<output>10.5</output>

<gadget id="calculator">18 + 10.5</gadget>
<output>28.5</output>

<gadget id="calculator">28.5 * 2</gadget>
<output>57</output>

<gadget id="calculator">57 - 10</gadget>
<output>47</output>

<result>47</result>