[Mr. K]

if the AREA is 12sq ft then it must be a 3x4 ft blanket

3+4 times 2 = 14

(two 3 ft sides and two 4 ft sides)

[Nepeta]

if the AREA is 12sq ft then it must be a 3x4 ft blanket

Or a 1 X 12 blanket. Or a 2 X 12 blanket. Etc...