jika luas selimut kerucut sama dengan 472,04 cm pangkat 2 dan jari jari sama dgn 8 cm (phi = 3,14), maka volume kerucut =.....

phi x r x s = 427,04
3,14 x 8 x s = 427,04
25,12 x s = 427,04
s = 17 cm

t = akar (s^2 - r^2) = 17^2 - 8^2 = 289 - 64 = akar (225) = 15 cm.

volume kerucut = 1/3 x phi x r x r x t
= 1/3 x 3,14 x 8 x 8 x 15
= 1004,8 cm^3