Answer: D, C, A, B
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Explanation:
- Rectangle A has area 4*3 = 12 square feet. Divide the number of blades of grass over this area to get a density of 34188/12 = 2849. So the density for rectangle A is 2849 blades per square foot. Put another way, one square foot of rectangle A contains about 2849 blades of grass.
- Rectangle B has area 5*4 = 20 square feet and density 56340/20 = 2817 blades per square foot.
- Rectangle C has area 6*3 = 18 square feet and density 52632/18 = 2924 blades per square foot.
- Rectangle D has area 4*2 = 8 square feet and density 25248/8 = 3156 blades per square foot.
The density order from greatest to least is therefore: D, C, A, B
