Rekensommen met erbij en eraf tot 20
In de mix
1.
13
12
–
=
2.
15
13
–
=
3.
19
18
–
=
4.
17
12
–
=
5.
17
12
–
=
6.
18
15
–
=
7.
15
13
–
=
8.
20
14
–
=
9.
12
1
+
=
10.
11
1
+
=
11.
12
7
+
=
12.
12
2
+
=
13.
19
14
–
=
14.
12
1
+
=
15.
15
13
–
=
16.
12
0
+
=
17.
13
2
+
=
18.
19
16
–
=
19.
12
0
+
=
20.
15
12
–
=
21.
15
14
–
=
22.
14
1
+
=
23.
15
13
–
=
24.
14
12
–
=