(ただし1と2を合せて12のような使い方は出来ません。)
21個の解法が見つかりました。
((7+(9-3))-3)=10
((7+9)-(3+3))=10
((7-(3-9))-3)=10
((7-3)+(9-3))=10
((7-3)-(3-9))=10
((9+(3×7))÷3)=10
((9+(7-3))-3)=10
((9-(3-7))-3)=10
((9-3)+(7-3))=10
((9-3)-(3-7))=10
(7+((9-3)-3))=10
(7+(9-(3+3)))=10
(7-((3+3)-9))=10
(7-(3+(3-9)))=10
(7-(3-(9-3)))=10
(9+((7-3)-3))=10
(9+(7-(3+3)))=10
(9-((3+3)-7))=10
(9-(3+(3-7)))=10
(9-(3-(7-3)))=10