Ex 12.2, 2

Transcript

Ex 12.2, 2 Find the area of a quadrant of a circle whose circumference is 22 cm. Area of quadrant = 1/4× area of circle = 1/4×("π"r2 ) Now, we need to find r. It is given that Circumference = 2πr 22 = 2πr 22/2 = πr 11 = πr 11/𝜋 = r r = 11/𝜋 r = 11/(22/7) r = 11 × 7/22 r = 7/2 cm Now, area of quadrant = 1/4×area of circle = 1/4("π"r2) = 1/4×22/7×(7/2)^2 = 1/4×22/7×(7 × 7)/(2 × 2) = 1/2×11/1×7/4 = 77/8 cm2