Find the Circumference of the Circle Whose Area is 81jrcm 2. - Mathematics

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Sum

Find the circumference of the circle whose area is 81π cm 2

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Solution

Area = π r2 

π r2 = 81 π 

r2 = 81

r = 9 cm

circumference = 2 πr

= 2 × π  × 9

= 18 π cm

araJmference - 18 π cm 

  Is there an error in this question or solution?
Chapter 19: Mensuration I - Exercise 19.1

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Frank ICSE Class 10 Mathematics Part 2
Chapter 19 Mensuration I
Exercise 19.1 | Q 26

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