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Question
Find the circumference of a circle whose area is 301.84 cm2.
Solution
Area of circle = 301.84 cm2.
et radius = r cm
Area of circle = 𝜋r2
𝜋r2 = 301.84
`22/7xxr^2` = 301.84
`r^2 = (301.84×7)/22 = (sqrt(7 × 7))^(1/2) × 13.75`
`r = sqrt(13.72 × 7) = sqrt(7 × 7 × 1.96) = 7 × 1.4 = 9.8` cm
Radius = r = 9.8 cm
Circumference = 2 × r = 2 ×`22/7`× 9.8
= 44 × 1.4
= 61.6 𝑐𝑚
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