12% is the markup and 7.99 is the average cost how much will it cost after the markup

as it is a markup, you multiple the cost by 1.12 (the 1 shows that the cost is increasing). the new cost is 8.9488 or $89.95 if you round.

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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