Решение задачи 66:

• $$84 - (36 + 24) : 3 \cdot 2 = 84 - 60 : 3 \cdot 2 = 84 - 20 \cdot 2 = 84 - 40 = 44$$
• $$187 - (87 - 40 - 17) \cdot 2 = 187 - (47 - 17) \cdot 2 = 187 - 30 \cdot 2 = 187 - 60 = 127$$
• $$(85 - 53) - (28 + 16) : 4 = 32 - 44 : 4 = 32 - 11 = 21$$
• $$271 \cdot 3 = 813$$
• $$408 \cdot 2 = 816$$
• $$129 \cdot 4 = 516$$
• $$28 : 4 \cdot 12 = 7 \cdot 12 = 84$$
• $$48 : 8 \cdot 13 = 6 \cdot 13 = 78$$
• $$35 : 5 \cdot 14 = 7 \cdot 14 = 98$$