Question 169792
A building is constructed over a circular pond.
The ratio from the longest side of the rectangular building is 4:3 and the perimeter is 280 units.
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4x+3x = 280
7x = 280
x = 40
length = 3x = 120 units
width = 4x = 160 units
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diagonal = sqrt[120^2+160^2] = 200 units
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Area = 120*160 = 19200 sq. units

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The edge of the pond is 4 units beyond each corner of the building on the diagonal when viewed in an aerial photo.
diameter of the pond = 200 +2*4 = 208 units
area of the pond = 104^2(pi) = 10816pi sq. units

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 The building owners plan to put water plants in the area of the pond that will recieve sunlight at noon.
That area = pond area - rectangle area = 10816pi - 19200 = 14779.47 sq. units
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 The plants cost $1.25 each and require a surface area of 30 square units to be healthy when mature. What is the total cost of the plants needed to cover the available area?
cost = [14779.47/30]*1.25 = 492.65*1.25 = $615.81
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Cheers,
Stan H.