A Sector of 56°, Cut Out from a Circle, Contains 17.6 Cm2. Find the Radius of the Circle. - Mathematics

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Sum

A sector of 56°, cut out from a circle, contains 17.6 cm2. Find the radius of the circle.

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Solution

Area of the sector = 17.6 cm

Area of the sector`=(pi"r"^2theta)/360`

`=> 17.6 =22/7xx"r"^2xx56/360`

`=> "r"^2 = (17.6 xx7xx360)/(22xx56)`

⇒ r =  6m

∴ Radius of the circle = 6 cm

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Chapter 18: Area of Circle, Sector and Segment - Exercise 18A [Page 820]

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RS Aggarwal Secondary School Class 10 Maths
Chapter 18 Area of Circle, Sector and Segment
Exercise 18A | Q 21 | Page 820

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