(ただし1と2を合せて12のような使い方は出来ません。)
17個の解法が見つかりました。
((4+7)-(5÷5))=10
((5×(7-4))-5)=10
((5+(5×7))÷4)=10
(4×(5÷(7-5)))=10
(4+(7-(5÷5)))=10
(4-((5÷5)-7))=10
(4÷((7-5)÷5))=10
(5×((4+5)-7))=10
(5×(4+(5-7)))=10
(5×(4-(7-5)))=10
(5×(4÷(7-5)))=10
(5×(5+(4-7)))=10
(5×(5-(7-4)))=10
(5÷((7-5)÷4))=10
(7+(4-(5÷5)))=10
(7-((5÷5)-4))=10