Test Your Head Place two aces, two kings, two queens, and two jacks in the format shown below such that no two cards of the same kind border on each other, every ace borders on a king, every king borders on a queen, every queen borders on a jack.
Borders can be horizontal or vertical, but never diagonal.
The key is position 6, since positions 7 and 8 touch position 6, but no other positions. If 6 is a jack, then 7 and 8 must be queens. Bu this is impossible, because the kings would then not be able to touch queens. Systematically trying possibilities leads to the above arrangement, or the A and J in positions 7 and 8 may be interchanged.