Adding Tens
20 + 30 =
50
4 + 12 =
16
23 + 13
36
26 + 28 =
57
8 + 4 + 3 =
15
60 + 20 =
80
23 + 7 =
30
16 + 32 =
48
26 + 16 =
42
2 + 9 + 9
20
40 + 40 =
80
35 + 6
41
60 + 17
77
61 + 29 =
90
21
30 + 40 =
70
57 + 7 =
64
41 + 52 =
93
48 + 37
85
18 + 12 + 4
34
80 + 20 =
100
78 + 9 =
87
66 + 33 =
99
83 + 17
100
23 + 7 + 31
61