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Question
Find the area and perimeter of the circles with following: Radius = 10.5cm
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Solution
The Area of a Circle with radius r = πr2
∴ The Area of a Circle with radius 10.5cm
= π(10.5)2
= `(22)/(7)(10.5)^2`
= 346.5cm2
The Circumference of a Circle with radius r = 2πr
The Circumference of a Circle with radius 10.5
= 2π(10.5)
= `2 xx (22)/(7)(10.5)`
= 66cm.
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