Final answer:
The perimeter of the square ballroom is 80m.
Step-by-step explanation:
To find the perimeter of a square, we need to know the length of one side. In this case, we know the area of the square ballroom is 400m². Since the area of a square is equal to the side length squared, we can find the side length by taking the square root of the area. √400 = 20. So, the side length of the square ballroom is 20m.
The perimeter of a square is calculated by multiplying the side length by 4. In this case, the perimeter would be 20m x 4 = 80m. Therefore, the perimeter of the square ballroom is 80m.
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