Volume suatu kerucut=8.316 cm*3 dan t= 18. Hitunglah panjang jari2??

V. Kerucut = 1/3 x π x r^2 x t
8316 = 1/3 x 3,14 x r^2 x 18
1/3 x 3,14 x r^2 x 18 = 8316
18.84 x r^2 = 8316
r^2 = 8316 / 18.84
r^2 = 441,40
r = √441,40
r = 21.01 cm