9514 1404 393
Answer:
1406.25 square yards
Step-by-step explanation:
To find the number of square yards represented by one square inch, divide the number of square yards by the number of square inches.
(9000 yd²)/(6.4 in²) = 1406.25 yd²/in²
Each square inch represents an area of 1406.25 square yards.
_____
Additional comment
The map scale is the square root of this number: 37.5 yards per inch, or ...
1 : 1350