7893怎么算24点

解题过程如下：
9 - 8 = 1
7 = 1 = 8
3 * 8 = 24
综上所述 （ 9 - 8 + 7 ）* 3 =2 4

1: (7 - 8 + 9) × 3
2: ((7 - 8) + 9) × 3
3: (7 - (8 - 9)) × 3
4: (7 + 9 - 8) × 3
5: ((7 + 9) - 8) × 3
6: (7 + (9 - 8)) × 3
7: (9 + 7 - 8) × 3
8: ((9 + 7) - 8) × 3
9: (9 + (7 - 8)) × 3
10: (9 - 8 + 7) × 3
11: ((9 - 8) + 7) × 3
12: (9 - (8 - 7)) × 3
13: 3 × (7 - 8 + 9)
14: 3 × ((7 - 8) + 9)
15: 3 × (7 - (8 - 9))
16: 3 × (7 + 9 - 8)
17: 3 × ((7 + 9) - 8)
18: 3 × (7 + (9 - 8))
19: 3 × (9 + 7 - 8)
20: 3 × ((9 + 7) - 8)
21: 3 × (9 + (7 - 8))
22: 3 × (9 - 8 + 7)
23: 3 × ((9 - 8) + 7)
24: 3 × (9 - (8 - 7))

(7-8+9)*3=24
((7-8)+9)*3=24
(7-(8-9))*3=24
(7+9-8)*3=24
((7+9)-8)*3=24
(7+(9-8))*3=24
(9+7-8)*3=24
((9+7)-8)*3=24
(9+(7-8))*3=24
(9-8+7)*3=24
((9-8)+7)*3=24
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