A room is 8 meters long, 5 meters wide, and 3 meters high. If you paste wallpaper on the four walls of the room, excluding doors and windows of 10 square meters, the wallpaper is 12.5 yuan per square meter. How much is the wallpaper in total?
一个房间长8米，宽5米，高3米，如果在房间四壁贴墙纸，除去门窗10平方米，每平方米墙纸12.5元，共要多少元的墙纸？
<gadget id="calculator">8 * 3</gadget>
<output>24</output>

<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<gadget id="calculator">24 + 15</gadget>
<output>39</output>

<gadget id="calculator">39 * 2</gadget>
<output>78</output>

<gadget id="calculator">78 - 10</gadget>
<output>68</output>

<gadget id="calculator">12.5 * 68</gadget>
<output>850</output>

<result>850</result>