Guest Posted May 25, 2009 Report Share Posted May 25, 2009 Three people are wearing different hats. If they exchange their hats in random, what is the chance that each of them would get a hat that is not their own? Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 25, 2009 Report Share Posted May 25, 2009 Lets say the hats are 1,2 and 3 for the corresponding persons. The only ways in which none would have the same hat after the exchange is 312 and 231. Two possible cases out of 6 possible combinations in which hats may be rearranged. So the probability is 1/3 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 25, 2009 Report Share Posted May 25, 2009 Lets say the hats are 1,2 and 3 for the corresponding persons. The only ways in which none would have the same hat after the exchange is 312 and 231. Two possible cases out of 6 possible combinations in which hats may be rearranged. So the probability is 1/3 You can't exchange a hat with yourself, I don't know if 321 is a possibility... Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 25, 2009 Report Share Posted May 25, 2009 Three people are wearing different hats. If they exchange their hats in random, what is the chance that each of them would get a hat that is not their own? The probability that the first gets a different hat is 2/3 The probability that the second and third get different hats is 1/2 therefore the total probability is 2/3 * 1/2 = 1/3 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 25, 2009 Report Share Posted May 25, 2009 Three people are wearing different hats. If they exchange their hats in random, what is the chance that each of them would get a hat that is not their own? if they are wearing their own hats to begin with, and do one random exchange, then the probability is 100%. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 26, 2009 Report Share Posted May 26, 2009 assuming that only one swap is made and you can not swap with your self then there is a 100% chance of getting a diferent hat, and if more then 1 trade is made there are three possible hats you can recive, only one of which is yours, so one out of three or 1/3 is your probibilty. Quote Link to comment Share on other sites More sharing options...
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Three people are wearing different hats.
If they exchange their hats in random, what is the chance that each of them would get a hat that is not their own?
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