Question

Find the circumference and area of a circle with a diameter of 22 inches. Leave your answers in terms of pi.

a. C = 11π; A = 44π
b. C = 22π; A = 44π
c. C = 11π; A = 121π
d. C = 22π; A = 121π

Answer 1

Radius is half diameter, i.e. 11 inches.
Circumference is 2 * pi * r
Area is pi * r^2.

Simple math right? :)

Answer 2

Just be reminded of this.
C = 2(pi)r
A = pi(r)^2

And radius is half of the diameter. :)

Answer 3

d. C = 22π; A = 121π then

Answer 4

Yes!