For any circle, the circumfrence \(C=2\pi r=\pi d\) where r is the radius and d is the diameter.
Use 20 inches for our radius in the formula \(C=2\pi r\).
\(C=2\pi \times20\)
Using π ≈ 3.14...
\(C\approx2\times3.14\times20\)
\(C\approx6.28\times20\)
\(\boxed{C\approx125.6\ inches}\)
