The Total solution for NCERT class 6-12
Circumferenceof the circle = 31.4 cm2πr = 31.4∴ r=31.4/(2×3.14) =5cmArea of the circle = 7πr2 = 3.14× 5 × 5 = 78.5 cm2Hence, the required radius = 5 cm and area = 78.5 cm2.