Question

circle A has a diameter of 9 cm. Circle b has a radius of 5 cm

Which circle has the larger circumference ?explain your reasoning

About how many centimeters larger is it?explain your reasoning

Answer 1

Circle B has a larger circumference.

Explanation:

Circumference of a circle is the diameter times pi.

C = pi•d

Circle B has radius 5, so its diameter is 10. Circle A has diameter of 9. A larger diameter will give a larger circumference.

C_circle A = 9pi

~= 28

While,

C_circle B = 10pi

~= 31

Circle B's circumference is about 3 cm larger. More accurately it's 1pi larger.