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