Calculating Card game odds while game is in play

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Eric!
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Calculating Card game odds while game is in play

Post by Eric! »

I know there is a lot of stuff on the internet but I'm just trying to sort out the basics of computing progressive odds as players play a game of cards. I've never been very good at permutations and combinations....

How do you calculate progressive odds?

Step 1:
For example from a 52 card deck I draw 1 card.
Odds that it is an ace is 4/52
It turns out to be an Ace of Spades.

Question:
What are the odds the next card is an ace?
3/51?

What if the other play drew a card before me?
Odds the next card is an ace--Would that be odds of pulling an ace 3/50 minus the odds that the other player took the ace before my turn? 3/50 - 3/51 ?
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Christopher
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Re: Calculating Card game odds while game is in play

Post by Christopher »

Yes, the odds each time are:

number of aces left in the deck
---------------------------------------------------
total number of cards left in the deck
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Eric!
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Re: Calculating Card game odds while game is in play

Post by Eric! »

So you don't think I should be subtracting the odds that the other player took the card before it was my deal?
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Christopher
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Re: Calculating Card game odds while game is in play

Post by Christopher »

Yes you should. You cannot know whether a desired card is still in the deck or has been dealt to another player. So you have to include both in denominator.
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