0
|
3268 Views
|
4 Replies
|
0 Total Likes
View groups...
Share
GROUPS:

# Probability question

Posted 11 years ago
 I would appreciate help with this question: What is the probability that two nine digit numbers, each using all of the digits 1 through 9, will have exactly two of the digits in the same place in the number?Thank you.-Ron
4 Replies
Sort By:
Posted 11 years ago
 Oh my. More complex than I had thought.Thank you very much.-Ron
Posted 11 years ago
 We could simulate an experiment with 10^5 random pairs: In:= N[Sum[a = RandomSample[Range]; b = RandomSample[Range];           Boole[Count[a - b, 0] == 2], {10^5}]/10^5]         Out= 0.18364 That's not too far from the exact probability In:= (1/2) Sum[(-1)^j/j!, {j, 0, 7}]Out= 103/560In:= N[%]  Out= 0.183929 See the following link for a proof: The Matching Problem.
Posted 11 years ago
 Not homework, I am having a debate with my adult son and neither of us knows how to answer the question.Thank you.-Ron
Posted 11 years ago
 Is there a Mathematica angle?   This sounds like homework.