A sector of a circle of radius 14 cm subtends an angle of 60° at the center. Calculate the perimeter of the sector. (Take π = 22/7)
Answer and explanation
Correct answer: B. 42.67 cm
- Step 1: Arc length: l = (θ / 360°) × 2πr = (60 / 360) × 2 × (22/7) × 14 = (1/6) × 88 = 14.67 cm. Step 2. Perimeter of sector includes two bounding radii: P = l + 2r = 14.67 + 2(14) = 14.67 + 28 = 42.67 cm. Answer: 42.67 cm. Why not the others: 14.67 cm is the arc length alone without the two radii; 28.00 cm is the sum of radii alone; 56.33 cm uses full circumference.
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