Think in Odds

One probability question is published each evening, US Eastern time, labelled with a category and difficulty; one example asks how a coin of unknown bias can yield a fair choice. Assumptions are stated explicitly, progressive hints are optional, a scratch area holds the solver's reasoning, and a worked solution follows. Past puzzles sit in an archive.

Languages

English

Daily puzzle

Yes

Unlimited mode

No

Archive

Yes

• 6.7
  RNGdle

  Roll a random number and collect badges
  Play
• 6.4
  Refiner

  Select digit groups that meet bucket rules
  Play
• 6.2
  Dozenal

  Merge numbered tiles built around twelve
  Play
• 6.1N
  Number Crunch

  Pop matching numbers in the fewest clicks
  Play
• 5.8
  Sequences

  Predict the next number in a sequence
  Play
• 5.8
  Octophobia

  Clear a number grid without making an 8
  Play
• 5.5
  FruitArena Daily

  Clear a number grid by boxing sums of ten
  Play
• 4.5
  RNGdle Daily

  Pick the rarest number in quick challenges
  Play