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Question
Find the area and perimeter of the circle with the following :
Diameter = 77 cm
Solution
Di am eter = 2 r
`=> "r" = "diameter"/2 = 77/2 = 38.5 "cm"`
Area of the circle = πr2
`= 22/7 xx 38.5 xx 38.5`
= 4658.5 cm2
Perimeter of the circle = 2πr
`= 2 xx 22/7 xx 38.5`
= 242 cm
Therefore, Area= 4658.5 cm2 and Perimeter= 242 cm
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