Question

the circumference of the compact disc is 28. 26 cm what is its radius

Answer 1

circumference=28.6

C=2×22/7×r

r=28.6×7/2×22

r=18.2

Answer 2

circumference =

$2\pi \: r$

$28.26 = 2 \times \frac{22}{7 } \times r$