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