Cards

2013-05-06

What is the chance of two cards with the same rank being next to each other if you draw n cards from a 52-card deck?

(Hint: the chance becomes >50% when n is 13)

Three cards in a row?

(Hint: the chance becomes >10% when n is 47)

Four?

(Hint: if you go through four shuffled decks, one at a time, looking for four in a row, the chance is <1%. With 5 decks, the chance is >1%)