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Forde
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Joined: November 27th, 2002, 7:45 pm

Cards question

May 12th, 2006, 11:39 am

Pick 3 cards from deck without replacement.What's prob that they're all of different suits, and no two numbers are consecutive,if we don't regard Ace and 1 as consecutive, or two numbers the same.I'll give talks from the recent conference to anyone who solves it
 
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markpark
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Joined: October 29th, 2005, 2:07 pm

Cards question

May 14th, 2006, 6:35 pm

i'm not definite on this but i'll give it a shot. the total number of ways you can pick 3 cards from the deck is 52 choose 3 = 52*51 *50.the number of ways each card can be a different suit is 4*3*2 = 24the number of ways each card is not consecutive and not the same is : well, the first card has 13 choices ( all the cards ), the next card has 11 ( so it's not consecutive with the other ) and the last card has 9 ( so it's not consecutive wtih either of the previous two ).so, the number of ways of satisfying the full criteria is : 24*(13*11*9).so, my answer is 24*(13*11*9)/(52*51*50).i would check with someone else though. i'm not positive about this. in fact, i think it's slightly off because, since ace and 2 are not considered consecutive, 13*11*9 may not be correct.