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 Question from Brooke, a student: What is the perimeter if the area is 20 ft?

Hi Brooke,

You can't tell the perimeter from the area. Many different shapes have an area of 20 square feet but different perimeters. For example a rectangle with dimensions 10 feet and 2 feet has an area of $10 \times 2 = 20$ square feet and its perimeter is $10 + 2 + 10 + 2 = 22$ feet. Likewise a rectangle with dimensions 5 feet and 4 feet has area 20 square feet and perimeter $5 + 4 + 5 + 4 = 18$ feet. What about a rectangle with dimensions 20 feet and 1 foot?

Penny

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