Diketahui keliling lingkaran 176 cm.Hitunglah diameter lingkaran tersebut

keliling = phi × diameter
diameter = keliling ÷ phi
diameter = 176 cm ÷ 22/7
diameter = 176 cm× 7/22
diameter = 56 cm

K = 2 × [tex] \pi [/tex] × r
176 = 2 × 22/7 × r
176 ÷ 2 × 7/22 = r
 28 cm = r

diameter = 28 cm × 2 = 56 cm