The area of the sector of a circle of radius 10.5 cm is 69.3 cm2. Find the central angle of the sector.
Given:
Radius of the circle = 10.5 cm
Area of the sector = 69.3 cm2
∵ Area of the sector = 
× πr2
∴ 69.3 = 
× 
× 10.5 × 10.5
θ = 69.3 × 360 × 
× 
× 
θ = 72°
Hence, the central angle is 72°.
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