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प्रश्न
Find the area and perimeter of the circles with following: Radius = 2.8cm
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उत्तर
The Area of a Circle with radius r = πr2
∴ The Area of a Circle with radius 2.8cm
= π(2.8)2
= `(22)/(7)(2.8)^2`
= 24.64cm2
The Circumference of a Circle with radius r = 2πr
The Circumference of a Circle with radius 2.8
= 2π(2.8)
= `2 xx (22)/(7)(2.8)`
= 17.6cm.
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