## Prealgebra (7th Edition)

$C=10\pi\approx 10\times3.14=31.4$ square cm
The circumference of a circle can be calculated as: $C=2r\pi=d\pi$ where r is the radius and d is the diameter. Here: $d=10$ cm $C=10\pi\approx 10\times3.14=31.4$ square cm.