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Question
The radius of a sector of a circle is 7 cm. If the measure of the arc of the sector is 210°, find the area of the sector in case.
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Solution
The radius of the sector of the circle, r = 7 cm
Measure of arc (θ) = 210°
∴ Area of the sector = `"θ"/360 × πr^2`
`= 210/360 × 22/7 × (7)^2`
`= 7/12 × 22 × 7`
`= 7/6 × 11 × 7`
= 89.83 cm2
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