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The formula for the area of a sector of a circle of radius r and angle theta (in degrees) is
A(theta/360) × pi × r squared
B(theta/180) × pi × r
Cpi × r × theta
D(theta/360) × 2 × pi × r
Answer & Solution
Correct answer: A. (theta/360) × pi × r squared
1. A full circle (360 degrees) has area pi × r squared.
2. A sector of angle theta is the fraction theta/360 of that.
3. Hence area = (theta/360) × pi × r squared.
_Source: NCERT Class 10 Mathematics, Ch 11 "Areas Related to Circles", §11.2_
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