Numbers
to 20
to 20
10 - 3 =
7
25 - 10 =
15
44 - 30 =
14
60 - 40 =
20
100 - 50 =
50
12 - 10 =
2
31 - 20 =
11
47 - 13 =
34
67 - 17 =
50
85 - 40 =
45
15 - 11 =
4
37 - 23 =
14
48 - 32 =
16
71 - 41 =
30
92 - 31 =
61
18 - 15 =
3
46 - 23 =
23
56 - 31 =
25
75 - 43 =
32
97 - 36 =
61
19 - 13 =
6
49 - 28 =
21
59 - 42 =
17
77 - 54 =
23
99 - 86 =
13