A SEQUENCE HIDDEN IN PLAIN SIGHT / 3 MINUTES
The station's last post
A station clerk dispatched a green, a blue, and a red envelope: one on Monday, one on Tuesday, and one on Wednesday. The ledger is smudged, but two notes survived.
The evidence
- Each colour was dispatched once, on a different day.
- The blue envelope was sent before the red envelope.
- The green envelope was sent exactly one day before the blue envelope.
Which envelope left on Tuesday?
Green · Blue · Red
A little hint
Try placing blue on Monday, then on Wednesday. Can both notes still hold?
Reveal the reasoning
Blue
Blue must be Tuesday. It cannot be Monday because green needs the day before; it cannot be Wednesday because red needs a later day. The complete order is green on Monday, blue on Tuesday, red on Wednesday.
All the information you need is in the clues. A useful way to solve this case is to test each possible answer against every fact, instead of choosing the first answer that feels plausible.
Try today's code-breaking puzzle ↗