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Can anyone tell me if The last one is right?

Can anyone tell me if The last one is right?-example-1
User Nicolas Finelli
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1 Answer

13 votes
13 votes

Answer:

See below.

Explanation:

All linear dimensions are in ft, and all areas are in ft².

Pyramid:

Lateral area: 4 × 6 × 5 / 2 = 60

Base area: 6 × 6 = 36

Total surface area: 96

Hidden surface area (the square base): 36

Actual surface area in the composite solid: 60

Square prism:

Lateral area: 4 × 20 × 6 = 480

Base area: 2 × 6 × 6 = 72

Total surface area: 552

Hidden surface area (both square bases): 72

Actual surface area in the composite solid: 480

Cube:

Total surface area: 6 × 6 × 6 = 216

Hidden surface area (one base): 36

Actual surface area in the composite solid: 180

The surface areas above are for each of the above solids if each were free standing and unattached to other solids.

The way the three components are above, you must deduct some areas of bases (as shown above in the actual surface areas) since they are internal.

Pyramid actual visible area: 60

Square prism actual visible area: 480

Cube: 180

Total surface area: 720

User Esac
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