(ただし1と2を合せて12のような使い方は出来ません。)
42個の解法が見つかりました。
((2×(7-1))-2)=10
((2×(7-2))÷1)=10
((2×2)+(7-1))=10
((2×2)-(1-7))=10
((2+(2+7))-1)=10
((2+2)+(7-1))=10
((2+2)-(1-7))=10
((2+7)+(2-1))=10
((2+7)-(1-2))=10
((2-1)+(2+7))=10
((2÷1)×(7-2))=10
((7+(2×2))-1)=10
((7+(2+2))-1)=10
((7-1)+(2×2))=10
((7-1)+(2+2))=10
((7-2)×(1×2))=10
((7-2)×(2÷1))=10
((7-2)÷(1÷2))=10
(1×(2×(7-2)))=10
(2×((1×7)-2))=10
(2×((7-2)÷1))=10
(2×((7÷1)-2))=10
(2×(1×(7-2)))=10
(2×(7-(1×2)))=10
(2×(7-(2÷1)))=10
(2+((2+7)-1))=10
(2+(2+(7-1)))=10
(2+(2-(1-7)))=10
(2+(7+(2-1)))=10
(2+(7-(1-2)))=10
(2-((1-2)-7))=10
(2-((1-7)-2))=10
(2-(1-(2+7)))=10
(2÷(1÷(7-2)))=10
(7+((2×2)-1))=10
(7+((2+2)-1))=10
(7+(2+(2-1)))=10
(7+(2-(1-2)))=10
(7-((1-2)-2))=10
(7-(1-(2×2)))=10
(7-(1-(2+2)))=10