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roro13us
Jan 24, 2010, 07:25 PM
Robby Billity shuffles a standard deck of cards (13 cards in each of four suits) and draws one card. Then Robby replaces the card, shuffles again, and draws another card. He repeats this procedure for a total of 1000 draws. About how many times would we expect Robby to draw these cards?

(a) the ace of spades (b) the 2 of clubs (c) a "face card" (jack, quieen, or king) in spades. (d) a face card in any suit

ebaines
Jan 25, 2010, 03:09 PM
The answers to these questions can be found by multiplying the numbefroif draws by the probability of pulling the card of interest on any one draw. I'll help you with the first question - see if that helps you understand how to do the others on your own.

There is one ace of spades in the deck, so the probability of pulling an ace of spades on any one draw is 1/52. So with 1000 draws you would expect to pull the ace of spades 1000 * 1/52 = 19.23 times.

Now, can you do the others?