V. kerucut = π × r^2 × t
V. kerucut = 22/7 × (42 ÷ 2)^2 × 18
V. kerucut = 22/7 × 21^2 × 18
V. kerucut = 22/7 × (21×21) × 18
V. kerucut = 22/7 × 441 × 18
V. kerucut = 24.948 ✔
V. kerucut = π × r^2 × t
V. kerucut = 22/7 × (42 ÷ 2)^2 × 18
V. kerucut = 22/7 × 21^2 × 18
V. kerucut = 22/7 × (21×21) × 18
V. kerucut = 22/7 × 441 × 18
V. kerucut = 24.948 ✔