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