Q1 of 18 Page 176

What is the area of a sector of central angle 120° in a circle of radius 3 centimetres? What is the area of a sector of the same central angle in a circle of radius 6 centimetres?

Radius = r = 3 cm


If x° is the angle at subtended at the sector,


Area of sector = r2


Here, x = 120°


∴ Area = π× 32cm2


If r2 = 6 cm


∴ Area = π× 62 = cm2


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