The Radius of Two Circles Are 20 Cm and 13 Cm. Find the Difference Between Their Circumferences. (Take π =22/7) - Mathematics

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Sum

The radius of two circles are 20 cm and 13 cm. Find the difference between their circumferences. (Take π =`22/7`)

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Solution

Radius of 1st circle = 20 cm

Circumference of the circle = 2πr

= `2xx22/7xx20`

= `40 xx 22/7`

= 125.7 cm

The radius of 2nd circle = 13 cm

Circumference of the circle = 2πr

= `2xx22/7xx13`

= `26 xx 22/7`

= 81.7

∴ The difference of circumference of two circles
= 125.7 − 81.7 cm = 44 cm

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Chapter 20: Mensuration - Exercise 20 (A)

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Selina Concise Mathematics Class 7 ICSE
Chapter 20 Mensuration
Exercise 20 (A) | Q 15

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