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