Umgekehrt plus oder minus rechnen

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85 + 14 = 99
99 = 85
        
74 - 22 = 52
52 = 74
85 + 14 = 99
99 - 14 =
        
74 - 22 = 52
52 + 22 =
85 + 14 = 99
- 14 = 85
        
74 - 22 = 52
+ 22 = 74
11 + 11 = 22
22 = 11
        
98 - 13 = 85
85 = 98
11 + 11 = 22
22 - 11 =
        
98 - 13 = 85
85 + 13 =
11 + 11 = 22
- 11 = 11
        
98 - 13 = 85
+ 13 = 98
44 + 44 = 88
88 = 44
        
67 - 31 = 36
36 = 67
44 + 44 = 88
88 - 44 =
        
67 - 31 = 36
36 + 31 =
44 + 44 = 88
- 44 = 44
        
67 - 31 = 36
+ 31 = 67
77 + 22 = 99
99 = 77
        
99 - 98 = 1
1 = 99
77 + 22 = 99
99 - 22 =
        
99 - 1 = 98
98 + 1 =
77 + 22 = 99
- 22 = 77
        
99 - 1 = 98
+ 1 = 99