addition no regrouping
20+13
33
29+48
77
34-12
22
80-43
37
200+312
512
18+31
49
33+57
90
46-32
14
62-48
14
435+312
747
25+31
56
58+43
101
89-47
42
82-46
36
147+258
405
44+44
88
78+12
90
58-52
6
72-56
16
302-90
212
62+13
75
49+31
80
78-43
35
81-78
3
856-492
364