Snelle erbijsommen en erafsommen tot 20
In de mix
1.
13
31
+
=
2.
1
27
+
=
3.
49
32
–
=
4.
20
1
–
=
5.
2
0
–
=
6.
14
36
+
=
7.
13
4
–
=
8.
13
28
+
=
9.
36
16
–
=
10.
26
12
–
=
11.
37
14
–
=
12.
21
19
–
=
13.
25
19
+
=
14.
45
3
+
=
15.
4
1
–
=
16.
9
4
–
=
17.
30
2
–
=
18.
47
1
+
=
19.
18
7
–
=
20.
22
12
+
=
21.
2
35
+
=
22.
1
1
–
=
23.
27
5
+
=
24.
48
1
+
=