Question 979457
Each floor of a square building has an area of 6.4×105 square feet.

What is the length of each side of the floor?
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64*105 = 6720 sq ft = s^2
s =~ 81.98 feet
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If the building has 12 stories, each with the same floor area, what is the total area of all of the floors?

6720*12 = 80640 square feet