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