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lumone
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Schools:St Gallen, Cambridge, HEC Montreal
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Official Guide PS-195 17 Mar 2007, 13:56
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Hello there,

Would anyone have a formula to explain the logic behind Official PS195?

Thank you

Ludo



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Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
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lumone
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Official Guide PS-195 17 Mar 2007, 16:31
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Tuneman
Could you post the problem?
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Unfortunately, there is a grid / picture in the problem... So, we have to refer to the book...
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lumone
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Official Guide PS-195 19 Mar 2007, 07:56
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lumone
Tuneman
Could you post the problem?

Unfortunately, there is a grid / picture in the problem... So, we have to refer to the book...
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It is a permutation problem: there must be 5 letters and the letters are either R or U. There must be 2R's and 3 U's.
Here's the solution:
UUURR
UURUR
UURRU
URUUR
URURU
URRUU
RRUUU
RUUUR
RUURU
RURUU

10 possible outcomes.

Would anyone have a strategy or formula instead?
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grad_mba
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Official Guide PS-195 19 Mar 2007, 14:03
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the formula is => 5! / (2! x 3!) = 10 :)

its a permutation problem with the objects being permutated are repetitive

n! / (r1! x r2! x ..)

n = total objects
r1 / r2 = different repetitions



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Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Problem Solving (PS) Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
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