21,333 1/3 ft²
The area of the rectangle on paper is the product of its length and width:
... (2 1/2 ft) × (1 1/3 ft) = (5/2×4/3) ft² = 10/3 ft²
The dimensions of the rectangle on the field are 80 times those on paper, so the area will be ...
... (80 × 2 1/2 ft) × (80 × 1 1/3 ft) = 80² × 10/3 ft² = 64000/3 ft²
... = 21,333 1/3 ft²
