Volume of frustum = (1/3)πh(R^2 + r^2 + Rr) = (1/3)π × 7 × (5^2 + 3^2 + 5 × 3) = (1/3)π × 7 × (25 + 9 + 15) = (1/3)π × 7 × 49 = 343π/3 cubic cm - Veritas Home Health