The probability of a flush A poker player holds a flush when all 5 cards in
the hand belong to the
same suit. We will find the probability of a flush when 5 cards are dealt.
Remember that a deck
contains 52 cards, 13 of each suit, and that when the deck is well shuffled,
each card dealt is equally likely to be any of those that remain in the deck.
(a) We will concentrate on spades. What is the probability that the first card
dealt is a spade? What
is the conditional probability that the second card is a spade given that the
first is a spade?
(b) Continue to count the remaining cards to find the conditional
probabilities of a spade on the third,
the fourth, and the fifth card given in each case that all previous cards are
spades.
(c) The probability of being dealt 5 spades is the product of the five
probabilities you have found.
Why? What is this probability?
(d) The probability of being dealt 5 hearts or 5 diamonds or 5 clubs is the
same as the probability of
being dealt 5 spades. What is the probability of being dealt a flush?