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Question
AC and BD are two perpendicular diameter of a circle ABCD. Given that the area of shaded portion is 308 cm2 calculate:
(i) The length of AC and
(ii) The circumference of circle
Solution
(i) Let r be the radius of the circle.
Then `1/2 π r^2` = 308
r2 = 308 x 2 x `7/22` = 142
r = 14 cm
Now, AC = 2r = 28 cm
(ii) Circumference = 2πr
Circumference = `22/7` x 28
Circumference = 88 cm
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