There is a bathroom in the shape of a cuboid, 4.6m long, 2.5m wide, and 2m high. If the four walls and the bottom surface are tiled, and the doors and windows are removed for 3.5m**2, how many square meters of tiles are needed at least?
有一个长方体形状的浴室，长4.6m，宽2.5m，高2m．如果将四壁和底面贴上瓷砖，除去门窗3.5m**2不贴，至少需要多少平方米的瓷砖？
<gadget id="calculator">9.2 + 5</gadget>
<output>14.2</output>

<gadget id="calculator">14.2 * 2</gadget>
<output>28.4</output>

<gadget id="calculator">28.4 - 3.5</gadget>
<output>24.9</output>

<gadget id="calculator">11.5 + 24.9</gadget>
<output>36.4</output>

<result>36.4</result>