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Formula for Area of circle :
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Area of a circle = πr²
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Find radius :
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1661.06 = 3.14 x r²
r² = 1661.06 ÷ 3.14
r² = 529
r = √529
r = 23 unit
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Formula for Circumference :
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Circumference = πD
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Find Circumference :
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Circumference = 3.14 x (2 x 23)
Circumference = 144.44 unit
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Answer: Circumference - 144.44 unit
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