Oefen met erbij en eraf tot 50
In de mix
1.
10
5
+
=
2.
20
5
+
=
3.
50
15
–
=
4.
30
15
+
=
5.
15
0
+
=
6.
15
0
+
=
7.
30
10
+
=
8.
20
25
+
=
9.
40
20
–
=
10.
15
0
+
=
11.
20
15
–
=
12.
25
10
+
=
13.
30
20
–
=
14.
30
10
+
=
15.
40
30
–
=
16.
15
20
+
=
17.
45
35
–
=
18.
15
15
+
=
19.
25
25
+
=
20.
35
20
–
=
21.
25
15
+
=
22.
15
0
+
=
23.
10
5
+
=
24.
20
25
+
=