Find the Circumference and Area of Circle of Radius 4.2 Cm - Mathematics

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Find the circumference and area of circle of radius 4.2 cm

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Solution

Radius (r) = 4.2 cm

Circumference = 2 × r

`= 2xx22/7xx4.2`

`= (44/10xx 6) = 264/10`

 = 26.4 𝑐𝑚

`Area = pir^2 = 22/7xx4.2xx4.2`

`=(22xx6xx42)/(10xx10)`

`=5544/100`

`55.44cm^2`

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Chapter 13: Areas Related to Circles - Exercise 13.1 [Page 12]

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RD Sharma Class 10 Maths
Chapter 13 Areas Related to Circles
Exercise 13.1 | Q 1 | Page 12

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