Find the area of a sector of angle 60 degrees in a circle of radius 21 cm. (Take pi = 22/7.)
Answer and explanation
Correct answer: D. 231 cm2
- Step 1: Area of sector = (angle/360) x pi x r^2 = (60/360) x 22/7 x 21 x 21. Step 2. = 231 cm2. Answer: 231 cm2. Why not the others: 1386 cm2: That is the area of the whole circle. 22 cm2: That is the arc length, not the area. 462 cm2: That doubles the correct fraction of the circle.
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