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Combinatorics

Why there are 1,326 starting hands, how many ways each can be dealt, and how the cards you can see remove combinations.

8 steps, as text. step through the interactive version →

  1. 01, open this step in the interactive version

    How many different two-card hands can you be dealt? Start with the deck: 52 cards.

  2. 02, open this step in the interactive version

    Your first card can be any of 52. Your second, any of the 51 left.

  3. 03, open this step in the interactive version

    But A♠ K♥ and K♥ A♠ are the same hand, so every hand was counted twice.

  4. 04, open this step in the interactive version

    Now one hand: ace–king. Four aces, four kings. Pair any ace with any king.

  5. 05, open this step in the interactive version

    Four of those share a suit: ace–king . The other twelve are .

  6. 06, open this step in the interactive version

    Pocket aces work differently. Pick two of the four aces. A♠A♥ and A♥A♠ are the same, so halve it.

  7. 07, open this step in the interactive version

    So you’re dealt ace–king almost three times as often as pocket aces.

  8. 08, open this step in the interactive version

    Cards you can see remove . These are called . Tap a card to show or hide it.