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