Project A: A 20-inch by 15-inch blueprint with a scale of 1 inch to 4 feet and a projected cost of $22,000.

20*15 = 300 square inches on blue print

With a 4 feet : 1 inch ratio:

300*4 = 1,200 square feet

22,000 / 1,200 = 11/6 = $18.33 per ft^2

Project B: A 10-inch by 8-inch blueprint with a scale of 1 inch to 8 feet and a projected cost of $25,000.

10*8 = 80 square inches on blue print

With a 8 feet : 1 inch ratio:

80*8 = 640 square feet

25,000 / 640 = 125/32 = $39.06 per ft^2

Project C: A 15-inch by 12-inch blueprint with a scale of 1 inch to 6 feet and a projected cost of $27,000.

15*12 = 180 square inches on blue print

With a 6 feet : 1 inch ratio:

180*6 = 1080 square feet

27,000 / 1080 = 25 per ft^2

Project D: An 8-inch by 6-inch blueprint with a scale of 1 inch to 12 feet and a projected cost of $30,000.

8*6 = 48 square inches on blue print

With a 12 feet : 1 inch ratio:

48*12 = 576 square feet

30,000 / 576 = 52.08 per ft^2

52.08 per ft^2 > $39.06 per ft^2 > 25 per ft^2 > $18.33 per ft^2

the order of the projects from greatest to least projected cost per square foot are:

Project D, Project B, Project C, Project A