Question

Find the value of the circumference of a circle with the given diameter.

3.21 ft

C=

(a) 1.61 pi
(b) 3.21 pi
(c) 6.42 pi

Answer 1

The circumference of a circle is the distance around the circle

Circumference is calculated using the formula:

Circumference = Pi multiplied by Diameter

If C = Circumference and D = Diameter, then

C = πD


If D =  3.21



C = π x 3.21


   = 3.21π

Answer 2

as we know, circumference = 2πr
Where r is the radius of given circle.
but if we have given diameter of circle.
Then, use formula of circumference = π × diameter
Because diameter = 2 × radius

Now, here given, diameter = 3.21 ft
so, circumference of circle = π × 3.21 ft
= 3.21 π ft

Hence, option (b) is correct