Need approach for this problem

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Need approach for this problem

by Tryingmybest » Tue Mar 24, 2009 11:05 am
I came across this question in Princeton . Unfortunately I reset the test. Please help me with the approach to this problem.

What is the probability of choosing four numbers 1, 2, 3, and 4 by four different persons A,B , C and D such that every Person chooses a distinct number?

I dont have a OA for this problem. But would like to know the approach.
Thanks!
Source: — Problem Solving |

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by devesh99 » Tue Mar 24, 2009 12:56 pm
Just trying

For selection of distinct numbers:
A can choose any of the 4 numbers (1,2,3,4) = 4
B can choose from any of the 3 remaining numbers = 3
C can choose from any of the 2 remaining numbers = 2
D can choose the last remaining number = 1
Therefore, 4*3*2*1 = 24

Now, for selection of numbers
A can select any of the 4 numbers = 4
B can select any of the 4 numbers = 4
C can select any of the 4 numbers = 4
D can select any of the 4 numbers = 4
Total chances = 4*4*4*4

Therefore Prability = 24/26 = 3/32

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by lilu » Tue Mar 24, 2009 3:13 pm
devesh99 wrote:Just trying



Therefore Prability = 24/26 = 3/32
I am sure you meant 24/246 :)

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by Tryingmybest » Tue Mar 24, 2009 4:11 pm
Thanks, I guess you are right. I remember an answer choice 10%

Appreciate your response.