(ただし1と2を合せて12のような使い方は出来ません。)
32個の解法が見つかりました。
((5+5)×(7÷7))=10
((5+5)+(7-7))=10
((5+5)-(7-7))=10
((5+5)÷(7÷7))=10
((5+7)+(5-7))=10
((5+7)-(7-5))=10
((5-7)+(5+7))=10
((7×(5+5))÷7)=10
((7+(5+5))-7)=10
((7-7)+(5+5))=10
((7÷7)×(5+5))=10
(5+((5×7)÷7))=10
(5+((5+7)-7))=10
(5+(5×(7÷7)))=10
(5+(5+(7-7)))=10
(5+(5-(7-7)))=10
(5+(5÷(7÷7)))=10
(5+(7×(5÷7)))=10
(5+(7+(5-7)))=10
(5+(7-(7-5)))=10
(5+(7÷(7÷5)))=10
(5-((7-5)-7))=10
(5-((7-7)-5))=10
(5-(7-(5+7)))=10
(7×((5+5)÷7))=10
(7+((5+5)-7))=10
(7+(5+(5-7)))=10
(7+(5-(7-5)))=10
(7-((7-5)-5))=10
(7-(7-(5+5)))=10
(7÷(7÷(5+5)))=10