Answer:
1728 cm²
Explanation:
The area of the model is the same as the area of the net shown.
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by color
Each blue rectangle is 10 cm by 24 cm, and there are two. Their area is ...
2×(10 cm)(24 cm) = 480 cm²
Each green rectangle is 12 cm by 24 cm, and there are three. Their area is ...
3×(12 cm)(24 cm) = 864 cm²
Each orange pentagon consists of a triangle 12 cm wide and (20-12) = 8 cm high, on top of a square 12 cm on a side. There are 2 of them. Their area is ...
2×((12 cm)² +1/2(12 cm)(8 cm)) = 384 cm²
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total
The model's total area is ...
blue area + green area + orange area = (480 +864 +384) cm² = 1728 cm²
Gavin will need 1728 cm² of paper to cover the entire model.