Surface Area of Composite 3D Figures Quick Check

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Question
Use the image to answer the question.

A giant model of a magnet is being built for a museum exhibit. What is the total surface area of the prop that will need to be painted if the depth of the magnet is 3 feet?

(1 point)
Responses

370 ft.2
370 ft. squared

180 ft.2
180 ft. squared

410 ft.2
410 ft. squared

330 ft.2

1 answer

To find the total surface area of the magnet, you would need to calculate the surface area of all the individual sides and then add them together.

The magnet is composed of 3 rectangular prisms: one large rectangle for the front (12 ft x 6 ft), one large rectangle for the back (12 ft x 6 ft), and a smaller rectangle for the side (12 ft x 3 ft).

Front and back: 2(12 ft x 6 ft) = 2(72 sq ft) = 144 sq ft
Sides: 2(12 ft x 3 ft) = 2(36 sq ft) = 72 sq ft

Total surface area = 144 sq ft + 72 sq ft = 216 sq ft

Therefore, the total surface area of the prop that will need to be painted is 216 ft^2.