The triangle Prism has 5 sides.
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Area of the bottom rectangle:
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Area = 15 x 20 = 300 ft²
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Area of the two triangles:
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Area = 2 [ 1/2 x 15 x 8] = 120 ft²
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Area of the top rectangle:
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Area = 20 x 17 = 340 ft²
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Area of the side rectangle:
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Area = 8 x 20 = 160 ft²
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Total Area
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300 + 120 + 340 + 160 = 920 ft²
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Answer: Total Surface area = 920 ft²
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