Question

If pi is rounded to a whole number, what is a reasonable estimate for the circumference of a circle with a diameter of 18 cm?

57 cm
50 cm
54 cm
56 cm

Answer 1

54 cm

Explanation:

Hi there!

1) Round pi

π = 3.14159265...

Rounded to a whole number ⇒ 3

2) Determine the circumference

C = πd where d is the diameter

Plug in the diameter

C = 18π

Plug in π

C = 18(3)

C = 54

Therefore, a reasonable estimate for the circumference of this circle would be 54 cm.

I hope this helps!