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A sector of 56°, cut out from a circle, contains 17.6 cm^{2}. Find the radius of the circle.

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#### Solution

Area of the sector = 17.6 cm^{2 }

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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