We can't really see the picture.
Can you add an attachment to the table, so we can see the prices.
The right approach to this problem is to first determine the real dimension by using the given scale factor.
width : (2.5 ft) x 250 = 625 ft
length: (2.0 ft) x 250 = 500 ft
The area of a rectangle is calculated by multiplying the length and the width.
A = (625 ft)(500 ft) ]= 312,500 ft²
Thus, the area of the actual castle in square feet is 312,500.