In a garden, seven flowers are to be arranged around a circular walk. Two arrangements of the flowers are considered different only when the positions of the flowers are different relative to each other. What is the total number of different possible arrangements of the flowers?
I obtained this question from
https://www.gmathacks.com/quant-topics/p ... ircle.html
but in my view the answer given is wrong.
The answer given is 720,
but shouldn't it be 360,
Solution:
n = 7
We can arrange this circular permutation in (n-1)! number of ways
Hence 6!
since the flowers are identical and will be the same from clockwise or counter-clockwise.
Answer is 6! / 2 = 360
Experts, please share your valued views.
Flowers in the Garden Permutatin
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For an explanation of circular permutations, check my post here:eaakbari wrote:In a garden, seven flowers are to be arranged around a circular walk. Two arrangements of the flowers are considered different only when the positions of the flowers are different relative to each other. What is the total number of different possible arrangements of the flowers?
I obtained this question from
https://www.gmathacks.com/quant-topics/p ... ircle.html
but in my view the answer given is wrong.
The answer given is 720,
but shouldn't it be 360,
Solution:
n = 7
We can arrange this circular permutation in (n-1)! number of ways
Hence 6!
since the flowers are identical and will be the same from clockwise or counter-clockwise.
Answer is 6! / 2 = 360
Experts, please share your valued views.
https://www.beatthegmat.com/seating-arra ... 85488.html
We divide by 2 only if the elements are to be arranged around a RING THAT CAN BE FLIPPED OVER. I posted an explanation here:
https://www.beatthegmat.com/counting-methods-t73853.html
Last edited by GMATGuruNY on Sun Nov 11, 2012 6:20 am, edited 1 time in total.
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I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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eaakbari wrote:In a garden, seven flowers are to be arranged around a circular walk. Two arrangements of the flowers are considered different only when the positions of the flowers are different relative to each other. What is the total number of different possible arrangements of the flowers?
I obtained this question from
https://www.gmathacks.com/quant-topics/p ... ircle.html
but in my view the answer given is wrong.
The answer given is 720,
but shouldn't it be 360,
Solution:
n = 7
We can arrange this circular permutation in (n-1)! number of ways
Hence 6!
since the flowers are identical and will be the same from clockwise or counter-clockwise.
Answer is 6! / 2 = 360
Experts, please share your valued views.
It is n!/n = 7!/7 = 720.
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