Obviously, the walls of the room need to be repainted. The room is 4 meters long, 3 meters wide, and 3 meters high. Excluding the door and window area of 4.6 square meters, 0.5 kilograms of paint is used per square meter. How many kilograms of paint are needed to paint a clearly painted room?
明明的房间四壁要粉刷一新，房间长4米，宽3米，高3米．除去门窗面积4.6平方米，每平方米用涂料0.5千克，粉刷明明房间约要多少千克涂料？
<gadget id="calculator">4 * 3</gadget>
<output>12</output>

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

<gadget id="calculator">12 + 9</gadget>
<output>21</output>

<gadget id="calculator">21 * 2</gadget>
<output>42</output>

<gadget id="calculator">42 - 4.6</gadget>
<output>37.4</output>

<gadget id="calculator">12 + 37.4</gadget>
<output>49.4</output>

<gadget id="calculator">49.4 * 0.5</gadget>
<output>24.7</output>

<result>24.7</result>