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