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Question
The circumference of a circle is equal to the perimeter of a square. The area of the square is 484 sq.m. Find the area of the circle.
Solution
Let the side of the square = s and the radius of the circle = r
∴ 2πr = 4s
But, the area of the square 484m2
∴ the side of the square
= `sqrt(484)`
= 22m
⇒ 2πr
= 4 x 22 ∈ r
= 14m
The Area of a Circle with radius r = πr2
The Area of a Circle with radius 14
= π(14)2
= `(22)/(7) xx (14)^2`
= 616m2.
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