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GnomeSain
Newbie

Posts: 1
 5 Card Magic Trick   « on: May 21st, 2011, 6:07pm » Quote Modify

By the pigeon-hole principle, you're going to have least a pair of the same suit.  Call these cards A and B. For simplicity suppose the ranks are just from 1 to 13.  We define the distance d(A,B) to be how many steps it to go from A forward mod 13 to B.  So for example, d(3,5) = 2 and d(9,3) = 7.  Then, for any A and B , we are guarenteed either d(A,B) is less than or equal to 6 or d(B,A) is less than or equal to 6.

If d(A,B) is less than or equal to 6, we will guess B and flip A on the fourth. If d(B,A) is less than or equal to 6, we will guess A and flip B on the fourth.

That means, the first three cards X,Y and Z will have to convey what d(A,B) or d(B,A) is.  We use the usual card ordering on them and note the total arrangement of orderings is 3! = 6.  So we have just enough to convey the distance from A to B.

 « Last Edit: May 21st, 2011, 6:10pm by GnomeSain » IP Logged
arun gupta
Newbie

hello friends :)

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Posts: 19
 Re: 5 Card Magic Trick   « Reply #1 on: Apr 3rd, 2012, 10:13pm » Quote Modify

I thought this is one of the best and easy trick. I tried and do it many times in a day.
Thanks!
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keithgilabert
Newbie

Keith Gilabert, "Life is but a dream."

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Posts: 40
 Keith Gilabert. 5 Card Magic Trick   « Reply #2 on: May 13th, 2012, 8:23pm » Quote Modify

That is a really cool trick!

Thanks,

Keith Gilabert
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RandyMagic
Newbie

Posts: 1
 Re: 5 Card Magic Trick   « Reply #3 on: Nov 13th, 2014, 2:37am » Quote Modify

Easy and cool trick! I tried myself and did not know it would be so much fun!
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