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