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