The Radii of Two Circles Are 19 Cm and 9 Cm, Find the Radius of the Circle Which Has Circumference Equal to the Sum of the Circumferences of the Two Circles. - Mathematics

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Sum

The radii of two circles are 19 cm and 9 cm, Find the radius of the circle which has circumference equal to the sum of the circumferences of the two circles.

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Solution

Let the radius of the required circle be r.

Now, Circumference of the required circle = Circumference of circle having radius 19 cm + Circumference of circle having radius 9 cm

⇒ 2πr = 2π × 19 + 2π × 9

⇒ r = 19 + 9

⇒ r = 28 cm

Hence, the radius of the required circle is 28 cm.

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Chapter 18: Area of Circle, Sector and Segment - Exercise 18A [Page 819]

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RS Aggarwal Secondary School Class 10 Maths
Chapter 18 Area of Circle, Sector and Segment
Exercise 18A | Q 11 | Page 819

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