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Question
The diameter of a circle is 28 cm.
Find its :
(i) Circumference
(ii) Area.
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Solution
Let r be the radius of the circle.
(i) 2r = 28 cm
circumference = 2πr
= 28π cm
= 88 cm
(ii) area = πr2
= π `(28/2)^2`
= 196π cm2
= 616 cm2
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