simple subtraction
10-5
5
What number is missing?
37- __=15
22
47-20
27
54-49
5
37+49=
86
15-5
10
What number is missing?
23-__=11
12
29-25
4
54-26
28
56+48
104
12-6
6
What number is missing?
38-__=21
17
41-34
7
84-67
17
58-39
19
40-20
20
What number is missing?
46-__=22
22
90-52
38
92-57
35
67-19
19
100-50
98-__=65
33
98-14
84
43-19
24
47+58
105