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Question
In a circle of radius 21 cm, an arc subtends an angle of 60° at the centre. Find the area of the sector formed by the arc. (Use π = `22/7`)
Solution
Radius of the circle (r) = 21 cm
Angle subtended by the given arc = 60°
Area of sector = `theta/360^@ xx pir^2`
= `(60°)/(360°) xx 22/7 xx (21)^2`
`= 1/6 xx 22/7 xx (21)^2`
`= 231` cm2
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