Question

The diameters of two concentric circles are 14 cm and 12 cm. The area of the region between them is :​

Answer 1

Diameter of Smaller Circle = 12 cm

Its radius (r) = 6 cm

Diameter of Bigger Circle = 14 cm

Its radius (R) = 7 cm

Area of region between them = Ar(Bigger Circle) - Ar(Smaller Circle)

=π$R^2$ - π$r^2$

= π($R^2$-$r^2$)

= $22/7$(49-36)

= (22 x 13)/7 = 286/7 = 40.85 $cm^2$