Reken de erafsommen tot 20 uit
Erafsommen
|
1.
12 – 6 =
6
10
|
2.
2 – 1 =
1
6
|
3.
9 – 7 =
2
7
|
4.
1 – 1 =
2
0
|
|
5.
8 – 2 =
1
6
|
6.
4 – 2 =
3
2
|
7.
2 – 1 =
5
1
|
8.
15 – 14 =
3
1
|
|
9.
15 – 13 =
2
4
|
10.
13 – 6 =
4
7
|
11.
13 – 1 =
14
12
|
12.
15 – 11 =
4
6
|
|
13.
5 – 2 =
3
4
|
14.
13 – 8 =
5
8
|
15.
20 – 20 =
4
0
|
16.
16 – 10 =
6
1
|
|
17.
9 – 9 =
4
0
|
18.
12 – 7 =
3
5
|
19.
2 – 2 =
3
0
|
20.
20 – 17 =
3
6
|