In a circle of radius 21 cm, an arc subtends an angle of 60° at the centre. The length of the arc is
Radius of Circle = R = 21 cm
Angle Subtended by the arc = 60°
Length of an arc of a sector of angle 
of a circle with radius R = 
Length of arc = 2 × 22/7 × 21 × 60/360 cm = 22 cm
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