(ただし1と2を合せて12のような使い方は出来ません。)
36個の解法が見つかりました。
(((5+9)-3)-1)=10
((5+(9-1))-3)=10
((5+(9-3))-1)=10
((5+9)-(1+3))=10
((5-(1-9))-3)=10
((5-(3-9))-1)=10
((5-1)+(9-3))=10
((5-1)-(3-9))=10
((5-3)+(9-1))=10
((5-3)-(1-9))=10
((9+(5-1))-3)=10
((9+(5-3))-1)=10
((9-(1-5))-3)=10
((9-(3-5))-1)=10
((9-1)+(5-3))=10
((9-1)-(3-5))=10
((9-3)+(5-1))=10
((9-3)-(1-5))=10
(5×((9÷3)-1))=10
(5+((9-1)-3))=10
(5+((9-3)-1))=10
(5+(9-(1+3)))=10
(5-((1+3)-9))=10
(5-(1+(3-9)))=10
(5-(1-(9-3)))=10
(5-(3+(1-9)))=10
(5-(3-(9-1)))=10
(9+((5-1)-3))=10
(9+((5-3)-1))=10
(9+(5-(1+3)))=10
(9-((1+3)-5))=10
(9-(1+(3-5)))=10
(9-(1-(5-3)))=10
(9-(3+(1-5)))=10
(9-(3-(5-1)))=10