An ancient vault can only be opened if a specific sequence of three colored gems—Red, Blue, and Green—is placed in a row. The Red gem cannot touch the Green gem. The Blue gem must be placed somewhere to the right of the Red gem. What is the correct sequence from left to right?
Red, Green, Blue
Blue must be to the right of Red, leaving two possibilities for the first position: Red or Green. If Green is first, the sequence is Green, Red, Blue (where Red touches Green, violating the rule) or Green, Blue, Red (where Blue is left of Red, violating the rule). Thus, Red must be first. Since Red cannot touch Green, Green cannot be second. Therefore, Green must be second and Blue third.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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