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