Wang Yiming is painting an advertising wall with a length of 5 meters and a width of 4 meters. Excluding a square neon lamp shade with a side length of 5 decimeters on the wall, how big is the area that needs to be painted?
王一名正在给一面长5米，宽4米的广告墙涂油漆，除去墙上一个边长为5分米的正方形霓虹灯罩，需要刷油漆的面积有多大？
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