A mathematical puzzle whose essential nature involves randomness. General probability questions are off-topic but some of them can be asked on Mathematics Stack Exchange with the [probability] tag.

A probability puzzle is a puzzle, usually mathematical, that involves uncertain outcomes.

Probability puzzles often involve , , or , although other mechanisms may act as sources of uncertain outcomes.

For example: Left coin, right coin, last coin?

Another example of a probability puzzle is the Monty Hall problem: the game show problem with three doors, one car, and two goats.

General probability questions are off-topic but can be asked on our sister site Mathematics Stack Exchange with the tag (some questions can be found here).