24点：[把给定的四个数，运用“+.-.X.÷”和乘法方等运算符号和括号，可以打乱顺序，算出的得数都等于24]

来源：百度知道 编辑：UC知道 时间：2024/05/24 17:27:22
《 4 5 7 9 》 《 3 7 8 8 》
《 2 2 8 8 》 《 3 3 7 7 》
《 1 3 5 7 》 《2 3 6 9》

《 4 5 7 9 》
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4×7+5-9 = 24
(4×7)+5-9 = 24
4×7+(5-9) = 24
(4×7+5)-9 = 24
(4×7)+(5-9) = 24
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4×7-9+5 = 24
(4×7)-9+5 = 24
(4×7-9)+5 = 24
4×7-(9-5) = 24
(4×7)-(9-5) = 24
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4×9-(5+7) = 24
(4×9)-(5+7) = 24
4×9-5-7 = 24
(4×9)-5-7 = 24
(4×9-5)-7 = 24
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4×9-(7+5) = 24
(4×9)-(7+5) = 24
4×9-7-5 = 24
(4×9)-7-5 = 24
(4×9-7)-5 = 24
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5+4×7-9 = 24
5+(4×7)-9 = 24
(5+4×7)-9 = 24
5+(4×7-9) = 24
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5+7×4-9 = 24
5+(7×4)-9 = 24
(5+7×4)-9 = 24
5+(7×4-9) = 24
5×(7-4)+9 = 24
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5-9+4×7 = 24
(5-9)+4×7 = 24
5-9+(4×7) = 24
(5-9)+(4×7) = 24
5-(9-4×7) = 24
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5-9+7×4 = 24
(5-9)+7×4 = 24
5-9+(7×4) = 24
(5-9)+(7×4) = 24
5-(9-7×4)