Precisely 7 boards are arranged in a straight line. Their colors are:
blue, brown, green, orange, purple, red, and yellow  albeit not necessarily in that order.
It is known that:
 Red is next to blue.
 Purple is somewhere to the left of green.
 There is precisely one board between yellow and red.
 There are exactly two boards between brown and blue.
 Blue is the 4th board from the left.
 Orange is directly between yellow and purple.
Determine the precise order of these seven boards.
Using rules 3 and 6, either purple/orange/yellow/***/red or red/***/yellow/orange/purple. Since rule 5 puts blue in the middle, purple will be either the first or the last board, and rule 2 makes it the first.
Then rule 4 places brown, green gets the remaining empty board so that the solution is:
purple/orange/yellow/blue/red/green/brown
Rule 1 isn't needed.

Posted by xdog
on 20220913 11:34:43 