3,5,7,8,结果等于20是怎么算

3,5,7,8,结果等于20是怎么算
3,5,7,8,结果等于20是怎么算

3,5,7,8,结果等于20是怎么算
（3+8-7）×5=20

1: 3 - (5 - 8) × 7
2: 3 - ((5 - 8) × 7)
3: 3 - (7 × (5 - 8))
4: 3 - 7 ×(5 - 8)
5: 3 × 7 - 5 + 8
6: (3 × 7) - 5 + 8
7: (3 × 7 - 5) + 8
8: ((3 × 7) - 5) + 8
9: 3...

全部展开

1: 3 - (5 - 8) × 7
2: 3 - ((5 - 8) × 7)
3: 3 - (7 × (5 - 8))
4: 3 - 7 ×(5 - 8)
5: 3 × 7 - 5 + 8
6: (3 × 7) - 5 + 8
7: (3 × 7 - 5) + 8
8: ((3 × 7) - 5) + 8
9: 3 × 7 -(5 - 8)
10: (3 × 7) - (5 - 8)
11: 3 + (7 × (8 - 5))
12: 3 + 7 ×(8 - 5)
13: 3 × 7 + 8 - 5
14: (3 × 7) + 8 - 5
15: (3 × 7 + 8) - 5
16: ((3 × 7) + 8) - 5
17: 3 × 7 +(8 - 5)
18: (3 × 7) + (8 - 5)
19: 3 + (8 - 5) × 7
20: 3 + ((8 - 5) × 7)
21: 5 × 7 -(3 + 8)
22: (5 × 7) - (3 + 8)
23: 5 × 7 - 3 - 8
24: (5 × 7) - 3 - 8
25: (5 × 7 - 3) - 8
26: ((5 × 7) - 3) - 8
27: 5 × 7 -(8 + 3)
28: (5 × 7) - (8 + 3)
29: 5 × 7 - 8 - 3
30: (5 × 7) - 8 - 3
31: (5 × 7 - 8) - 3
32: ((5 × 7) - 8) - 3
33: 7 × 3 - 5 + 8
34: (7 × 3) - 5 + 8
35: (7 × 3 - 5) + 8
36: ((7 × 3) - 5) + 8
37: 7 × 3 -(5 - 8)
38: (7 × 3) - (5 - 8)
39: 7 × 3 + 8 - 5
40: (7 × 3) + 8 - 5
41: (7 × 3 + 8) - 5
42: ((7 × 3) + 8) - 5
43: 7 × 3 +(8 - 5)
44: (7 × 3) + (8 - 5)
45: 7 × 5 -(3 + 8)
46: (7 × 5) - (3 + 8)
47: 7 × 5 - 3 - 8
48: (7 × 5) - 3 - 8
49: (7 × 5 - 3) - 8
50: ((7 × 5) - 3) - 8
51: 7 × 5 -(8 + 3)
52: (7 × 5) - (8 + 3)
53: 7 × 5 - 8 - 3
54: (7 × 5) - 8 - 3
55: (7 × 5 - 8) - 3
56: ((7 × 5) - 8) - 3
57: (7 × (8 - 5)) + 3
58: 7 × (8 - 5) + 3
59: 8 + 3 × 7 - 5
60: (8 + 3 × 7) - 5
61: (8 + (3 × 7)) - 5
62: 8 + (3 × 7) - 5
63: 8 + (3 × 7 - 5)
64: 8 + ((3 × 7) - 5)
65: 8 - 5 + 3 × 7
66: (8 - 5) + 3 × 7
67: 8 - 5 +(3 × 7)
68: (8 - 5) + (3 × 7)
69: 8 - (5 - 3 × 7)
70: 8 - (5 - (3 × 7))
71: 8 - 5 + 7 × 3
72: (8 - 5) + 7 × 3
73: 8 - 5 +(7 × 3)
74: (8 - 5) + (7 × 3)
75: 8 - (5 - 7 × 3)
76: 8 - (5 - (7 × 3))
77: (8 - 5) × 7 + 3
78: ((8 - 5) × 7) + 3
79: 8 + 7 × 3 - 5
80: (8 + 7 × 3) - 5
81: (8 + (7 × 3)) - 5
82: 8 + (7 × 3) - 5
83: 8 + (7 × 3 - 5)
84: 8 + ((7 × 3) - 5)

收起

[(8-7)+3]×5=20

[8-(7-3)]*5

98+7-6+5-4+3-2-1=100 如果只能添加+ - 的话是不可能的，就算全部都是+，最多也就只有45 如果可以把2个数字合到一起 那么： 98+7-