1:4 × (5 - 6 + 7)2:4 × ((5 - 6) + 7)3:4 × (5 - (6 - 7))4:4 × (5 + 7 - 6)5:4 × ((5 + 7) - 6)6:4 × (5 + (7 - 6))7:4 × (7 + 5 - 6)8:4 × ((7 + 5) - 6)9:4 × (7 + (5 - 6))10:4 × (7 - 6 + 5)11:4 ×...