Question

A. 28.26cm
B. 37.68cm
C. 18.84cm
D. 56.52cm

Answer 1

D. 56.52 cm

Explanation:

Circumference = 2*pi*r

Based on the picture, we can see the largest circle has a diameter of 18 cm. (12 + 6)

The radius of the largest circle is half of it's diameter: 18/2 = 9 cm

Now put in the numbers for the circumference equation:

Circumference = 2 * pi * 9 (9 is the radius)

Circumference = 56.5 cm

Answer 2

Option D

Explanation:

circumference: 2pi x r

r = 9 (6 + 12)/ 2

2 x pi x 9

= 18 pi cm^2 = 56.55 cm^2