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