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