有以下这些种计算方法都能得到24:
6×((7+9)-12)=24
6×(7+(9-12))=24
6×(7-(12-9))=24
6×((7-12)+9)=24
(6×(9-7))+12=24
6×((9+7)-12)=24
6×(9+(7-12))=24
6×(9-(12-7))=24
6×((9-12)+7)=24
(7+(9-12))×6=24
(7-(12-9))×6=24
((7-12)+9)×6=24
((9-7)×6)+12=24
((9+7)-12)×6=24
(9+(7-12))×6=24
(9-(12-7))×6=24
((9-12)+7)×6=24
12-(6×(7-9))=24
12+(6×(9-7))=24
12-((7-9)×6)=24
12+((9-7)×6)=24