Find the Diameter of a Circle Whose Circumference is Equal to the Sum of Circumference of Circles with Radius 10 Cm, 12 Cm, and 18 Cm. - Mathematics

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Sum

Find the diameter of a circle whose circumference is equal to the sum of circumference of circles with radius 10 cm, 12 cm, and 18 cm.

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Solution

Let the radius of the circle = R cm

∴ 2πR = 2π × 10 + 2π × 12 + 2π × 18

On dividing each term by 2π, we get:

R = 10 + 12 + 18 = 40 cm

∴ Radius of the circle obtained = 40 cm

And, its diameter = 2 × Radius

= 2 × 40 cm = 80 cm

  Is there an error in this question or solution?
Chapter 20: Mensuration - Exercise 20 (A)

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Selina Concise Mathematics Class 7 ICSE
Chapter 20 Mensuration
Exercise 20 (A) | Q 19

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