Answer:
1900 cm²
Explanation:
We can use the given ratios and volume to find the scale factor for the dimensions. Knowing the dimensions, we can compute the surface area using the formula for a cuboid.
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dimensions
Let k represent the scale factor. Then the actual dimensions will be 5k, 4k, and 2k. The actual volume will be ...
V = LWH
5000 cm³ = (5k)(4k)(2k) = 40k³
k³ = (5000 cm³)/40 = 125 cm³
k = ∛(125 cm³) = 5 cm
The cuboid dimensions are 5(5 cm) = 25 cm, 4(5 cm) = 20 cm, and 2(5 cm) = 10 cm.
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area
The surface area of the cuboid can be computed from ...
A = 2(LW +H(L +W))
A = 2((25 cm)(20 cm) +(10 cm)(25 +20 cm))
A = 2(500 cm² +(10 cm)(45 cm)) = 2(950 cm²) = 1900 cm²
The surface area of the cuboid is 1900 cm².