Three Chests
Three chests: gold, silver and bronze. The treasure is in one of them. Exactly one of these labels is true. Gold: 'The treasure is in here.' Silver: 'The treasure is not in here.' Bronze: 'The treasure is not in the gold chest.' Which chest holds the treasure?
Try each chest and count the true labels.
SILVER
If it were in gold or bronze, two labels would be true. Only silver leaves exactly one true label (bronze's).
How to solve it
Test each chest in turn and count how many labels come out true.
If the treasure is in gold, the gold label is true and the silver label ("not in here") is also true: two true labels, too many. If it is in bronze, the silver label and the bronze label are both true: two again.
If it is in silver, the gold label is false, the silver label is false, and the bronze label is true: exactly one.
The usual slip is trusting the gold label because it sounds confident. The treasure is in the silver chest.
Learn the method: Three Chests Riddle: Only One Label Is True. Which Chest?
