Let multiplicative factor for length and width be x
Then length = 7x, and width = 3x
Perimeter of field: 2(7x + 3x) = 2(10x) = 20x
Walking at 4 mph for 1 hour and 15 min, or for, we get:
With x being, length = , and width =
Since acreage denotes AREA, we get area as: