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