1:(3 + 1 + 2) × 42:((3 + 1) + 2) × 43:(3 + (1 + 2)) × 44:(3 + 1) × (2 + 4)5:3 × 1 × 2 × 46:(3 × 1) × 2 × 47:(3 × 1 × 2) × 48:((3 × 1) × 2) × 49:(3 × (1 × 2)) × 410...