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