Volume kerucut 6930 cm cubik dan tingginya 15 cm berapa panjang diameternya

Volume kerucut = 1/3 × 22/7 × r^2 × t
6930 = 1/3 × 22/7 × r^2 × 15
r^2 = (6930×7) / (22×5)
r^2 = 441
r = akar 441
r = 21 cm
jadi diameter = 2 x r
= 2 x 21 = 42 cm