The circumference of a circular swimming pool is 100 feet. If the radius of the pool is doubled, what will the new circumference be?

The new circumference is 200

Circumference, C = 2πr

Solve for r

C = 2πr

100 = 2πr

100/2π = r

15.92 ft = circumference of circle with C = 100ft

Doubled radius

15.92 (2) = 31.83 ft = new radius

C of new circle = 2πr

C = 2π (31.83)

[C = 200 ft]

= Circumference of new circle with doubled radius.