Math 221 Card Problems: Solutions A standard 52-card deck consists of 13 cards from each of 4 suits (spades, hearts, diamonds, clubs). The 13 cards have value 2 through 10, jack (J), queen (Q), king (K), or ace (A). Each value is a “kind” of card. The jack, queen, and king are called “face cards”. Note: All of the names of hands listed below are completely fictitious, so your answers do not need to be mutually disjoint. 1. How many 5-card hands contain a Face Place, i.e. all face cards? There are 12 total face cards, from which we must choose 5. 12 792 5 2. How many 5-card hands contain a Rainbow, i.e. include all four suits? There must be 2 cards from one suit and 1 card each from the other three suits. 4 13 3 13 685, 464 1 2 3. Suppose the ace of spades is removed from the deck, i.e. now there are only 51 cards being used. How many 5-card hands (from these 51) are a full house, i.e. three cards of one kind and two cards of another kind? There are three disjoint cases: (1) the 3 remaining aces are the three of a kind, (2) 2 of the aces are the pair, or (3) there are no aces in the hand. 12 4 3 12 4 12 4 11 4 3384 1 2 2 1 3 1 3 1 2 The following problems involve 6-card hands. 4. How many total 6-card hands are there? 52 20,358,520 6 5. How many 6-card hands contain a Rainbow, i.e. include all four suits? There are two disjoint cases: (1) 3 cards from one suit and 1 card each from the other three suits or (2) 2 cards each from two suits and 1 card each from the other two suits. 4 13 3 4 13 2 13 13 2,592, 460 1 3 2 2 6. How many 6-card hands contain a Triple Double, i.e. three distinct pairs? 3 13 4 61, 776 3 2 7. Suppose that the queens are “female” cards and that both kings and jacks are “male” cards. How many 6-card hands contain a Triple Date, i.e. three male cards and three female cards? There are 8 total male cards from which we must choose 3, and 4 total female cards from which we must choose 3. 8 4 224 3 3 8. How many 6-card hands contain a Crowded House, i.e. three cards of one kind, two cards of a second kind, and one card of a third kind? 13 4 12 4 11 4 164, 736 1 3 1 2 1 1