Question

用4，7，8，9算24点

用多种方法把4，7，8，9凑成24

Answer 1

1: 4 × (7 + 8 - 9)
2: 4 × ((7 + 8) - 9)
3: 4 × (7 + (8 - 9))
4: 4 × (7 - 9 + 8)
5: 4 × ((7 - 9) + 8)
6: 4 × (7 - (9 - 8))
7: 4 × (8 + 7 - 9)
8: 4 × ((8 + 7) - 9)
9: 4 × (8 + (7 - 9))
10: (4 + 8) × (9 - 7)
11: 4 × (8 - 9 + 7)
12: 4 × ((8 - 9) + 7)
13: 4 × (8 - (9 - 7))
14: (7 + 8 - 9) × 4
15: ((7 + 8) - 9) × 4
16: (7 + (8 - 9)) × 4
17: (7 - 9 + 8) × 4
18: ((7 - 9) + 8) × 4
19: (7 - (9 - 8)) × 4
20: (8 + 4) × (9 - 7)
21: (8 ÷ (7 - 4)) × 9
22: 8 ÷ (7 - 4) × 9
23: 8 ÷ ((7 - 4) ÷ 9)
24: (8 + 7 - 9) × 4
25: ((8 + 7) - 9) × 4
26: (8 + (7 - 9)) × 4
27: (8 - 9 + 7) × 4
28: ((8 - 9) + 7) × 4
29: (8 - (9 - 7)) × 4
30: 8 × (9 ÷ (7 - 4))
31: 8 × 9 ÷(7 - 4)
32: (8 × 9) ÷ (7 - 4)
33: (9 - 7) × (4 + 8)
34: (9 ÷ (7 - 4)) × 8
35: 9 ÷ (7 - 4) × 8
36: 9 ÷ ((7 - 4) ÷ 8)
37: (9 - 7) × (8 + 4)
38: 9 × (8 ÷ (7 - 4))
39: 9 × 8 ÷(7 - 4)
40: (9 × 8) ÷ (7 - 4)

Answer 2

第一个4
×
(7
+
8
-
9)第二 个(4
+
8)
×
(9
-
7)觉得不错请采纳~~要是还需要其他的请继续追问

Answer 3

8*[9/(7-4)=24

Answer 4

(8+4）X（9—7）=12X2=24

Answer 5

1:
8
×
(9
÷
(10
-
7))
2:
8
×
9
÷(10
-
7)
3:
(8
×
9)
÷
(10
-
7)
4:
(8
÷
(10
-
7))
×
9
5:
8
÷
(10
-
7)
×
9
6:
8
÷
((10
-
7)
÷
9)
7:
9
×
(8
÷
(10
-
7))
8:
9
×
8
÷(10
-
7)
9:
(9
×
8)
÷
(10
-
7)
10:
(9
÷
(10
-
7))
×
8
11:
9
÷
(10
-
7)
×
8
12:
9
÷
((10
-
7)
÷
8)