To calculate the surface area of the box that needs to be decorated (the front, two sides, and the top), we will first find the areas of each relevant section.
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Front Face Area:
- Length × Height = 27 cm × 20 cm = 540 cm².
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Top Face Area:
- Length × Width = 27 cm × 20 cm = 540 cm².
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Left Face Area:
- Width × Height = 20 cm × 20 cm = 400 cm².
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Right Face Area (identical to the Left Face):
- Width × Height = 20 cm × 20 cm = 400 cm².
Now, we will add the areas of these sections together to get the total surface area that needs to be decorated:
- Total Area = Front Face + Top Face + Left Face + Right Face
- Total Area = 540 cm² + 540 cm² + 400 cm² + 400 cm²
- Total Area = 540 + 540 + 400 + 400 = 1,880 cm².
Thus, the surface area of the box that needs to be decorated is 1,880 cm².