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