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### Complexity=9, Mode=1

Add. Press TAB or ENTER to move to the next problem.
 1.   1 + 4 = 2.   1 + 2 =

### Complexity=9, Mode=2

Add. Press TAB or ENTER to move to the next problem.
 1.   2 + 8 = 2.   2 + 3 =

### Complexity=9, Mode=3

Add. Press TAB or ENTER to move to the next problem.
 1.   3 + 3 = 2.   3 + 9 =

### Complexity=9, Mode=4

Add. Press TAB or ENTER to move to the next problem.
 1.   4 + 4 = 2.   4 + 7 =

### Complexity=9, Mode=2-4

Add. Press TAB or ENTER to move to the next problem.
 1.   4 + 1 = 2.   4 + 4 =

### Complexity=9, Mode=5

Add. Press TAB or ENTER to move to the next problem.
 1.   5 + 6 = 2.   5 + 4 =

### Complexity=9, Mode=6

Add. Press TAB or ENTER to move to the next problem.
 1.   6 + 7 = 2.   6 + 8 =

### Complexity=9, Mode=7

Add. Press TAB or ENTER to move to the next problem.
 1.   7 + 9 = 2.   7 + 4 =

### Complexity=9, Mode=5-7

Add. Press TAB or ENTER to move to the next problem.
 1.   7 + 9 = 2.   7 + 3 =

### Complexity=9, Mode=8

Add. Press TAB or ENTER to move to the next problem.
 1.   8 + 6 = 2.   8 + 1 =

### Complexity=9, Mode=9

Add. Press TAB or ENTER to move to the next problem.
 1.   9 + 4 = 2.   9 + 9 =

### Complexity=10, Mode=8-10

Add. Press TAB or ENTER to move to the next problem.
 1.   8 + 2 = 2.   10 + 5 =

### Complexity=10

Add. Press TAB or ENTER to move to the next problem.
 1.   2 + 10 = 2.   6 + 7 =

### Complexity=12

Add. Press TAB or ENTER to move to the next problem.
 1.   10 + 2 = 2.   1 + 3 =

### Complexity=15

Add. Press TAB or ENTER to move to the next problem.
 1.   5 + 14 = 2.   8 + 9 =

### Complexity=17

Add. Press TAB or ENTER to move to the next problem.
 1.   14 + 15 = 2.   5 + 15 =

### Complexity=20

Add. Press TAB or ENTER to move to the next problem.
 1.   6 + 18 = 2.   4 + 20 =

### Complexity=9, Mode=1

Add. Press TAB or ENTER to move to the next problem.
11 + 4 =
21 + 2 =

### Complexity=9, Mode=2

Add. Press TAB or ENTER to move to the next problem.
12 + 8 =
22 + 3 =

### Complexity=9, Mode=3

Add. Press TAB or ENTER to move to the next problem.
13 + 3 =
23 + 9 =
Solution
3 + 10 = 13
13 - 1 = 12

### Complexity=9, Mode=4

Add. Press TAB or ENTER to move to the next problem.
14 + 4 =
24 + 7 =

### Complexity=9, Mode=2-4

Add. Press TAB or ENTER to move to the next problem.
14 + 1 =
24 + 4 =

### Complexity=9, Mode=5

Add. Press TAB or ENTER to move to the next problem.
15 + 6 =
25 + 4 =

### Complexity=9, Mode=6

Add. Press TAB or ENTER to move to the next problem.
16 + 7 =
26 + 8 =
Solution
6 + 10 = 16
16 - 2 = 14

### Complexity=9, Mode=7

Add. Press TAB or ENTER to move to the next problem.
17 + 9 =
Solution
7 + 10 = 17
17 - 1 = 16
27 + 4 =

### Complexity=9, Mode=5-7

Add. Press TAB or ENTER to move to the next problem.
17 + 9 =
Solution
7 + 10 = 17
17 - 1 = 16
27 + 3 =

### Complexity=9, Mode=8

Add. Press TAB or ENTER to move to the next problem.
18 + 6 =
28 + 1 =

### Complexity=9, Mode=9

Add. Press TAB or ENTER to move to the next problem.
19 + 4 =
29 + 9 =
Solution
9 + 10 = 19
19 - 1 = 18

### Complexity=10, Mode=8-10

Add. Press TAB or ENTER to move to the next problem.
18 + 2 =
210 + 5 =

### Complexity=10

Add. Press TAB or ENTER to move to the next problem.
12 + 10 =
26 + 7 =

### Complexity=12

Add. Press TAB or ENTER to move to the next problem.
110 + 2 =
21 + 3 =

### Complexity=15

Add. Press TAB or ENTER to move to the next problem.
15 + 14 =
28 + 9 =
Solution
8 + 10 = 18
18 - 1 = 17

### Complexity=17

Add. Press TAB or ENTER to move to the next problem.
114 + 15 =
25 + 15 =
Solution
```  1
5
+ 15
20
```

### Complexity=20

Add. Press TAB or ENTER to move to the next problem.
```  1