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