What number comes next
5
14
17
18
11
=
=
=
=
=
What number comes before
=
=
=
=
=
7
17
6
18
14
Friends of Five
2
+
=
5
4
+
=
5
3
+
=
5
1
+
=
5
5
+
=
5
Buddies to Ten
6
+
=
10
5
+
=
10
3
+
=
10
7
+
=
10
2
+
=
10
Double Trouble
4
+
4
=
6
+
6
=
2
+
2
=
7
+
7
=
8
+
8
=