Diameter 10 brp jari jari dan keliling?

R = d : 2
r = 10 : 2
r = 5

K = 2 × phi × r
= 2 × 3,14 × 5
= 31,4 cm

Diameter 10 = jari-jari nya 5
keliling nya = π x diameter = 3.14 x 10 = 31.4