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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 cm^{2}

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