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Question
Find the area and perimeter of the following semi-circle :
Diameter= 5.6 cm
Solution
Diameter= 2 r
`=> "r" = "diameter"/2 = 5.6/2 = 2.8` cm
Area of the semi-circle =`1/2 pi "r"^2`
`= 1/2 xx 22/7 xx 2.8 xx 2.8`
= 12.32 cm2
Peri meter of the semi-cir de = (π r + 2r)
`= (22/7 xx 2.8) + (2 xx 2.8)`
= 14.4 cm
Therefore, Area = 12.32 cm2 and Peri meter = 14. 4 cm
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