ADDITION Self-Correcting Quiz - TWOS

1
5
+  2
2
8
+  2
3
2
+  8
4
4
+  2
5
2
+  2
6
7
+  2
7
2
+  2
8
2
+  7
9
1
+  2
10
2
+  5
11
2
+  1
12
0
+  2
13
3
+  2
14
2
+  3
15
6
+  2
16
2
+  4
17
2
+  9
18
2
+  6
19
9
+  2
20
2
+  0