I am not sure whether I understood the question but:moneyman wrote:Pls explain
5 people in a circle can sit (n-1)! ways
4! = 24 ways
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logitech
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5 people in a circle can sit (n-1)! ways
4! = 24 ways
LGTCH
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sudhir3127
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even i go with 24..logitech wrote:I am not sure whether I understood the question but:moneyman wrote:Pls explain
5 people in a circle can sit (n-1)! ways
4! = 24 ways
formula " N people arranged in a circle js ( n-1)!
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jackcrystal
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logitech
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wow thanks. So next time I see a question like this I will remember your "24".jackcrystal wrote:24
Awesome!
LGTCH
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logitech
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cramya wrote:Logitech,
Remember my 24 too
24
I have added the smilies at the end just for u man.(so that u can rememeber in a happy state)
Dear Diary, there are so many funny guys in this forum. One of them is called Cramya LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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jimmiejaz
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Guys, the question just gave the definition of a circular permutation in a tricky way. It says the arrangement is different only when the guys position is changed relative to one another.
And in circular permutation, the position relative to one another is same clockwise or anticlockwise.
So, it just asks the no of arrangements in a circular permutation and that is indeed 24 as explained by logitech.
Hope it helps!!!!
And in circular permutation, the position relative to one another is same clockwise or anticlockwise.
So, it just asks the no of arrangements in a circular permutation and that is indeed 24 as explained by logitech.
Hope it helps!!!!
What if i have not yet beat the beast, I know i will beat it!!!!!!!!
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GMATters1001
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Not knowing the formula for circular permutations:
5 people can be arranged 5! ways, however, since their relation to one another doesn't matter means that for every arrangement, there will be 4 others (5 total i.e. seats at the table) that are considered the same. thought of as an anagram,
12345 is the same as:
51234
45123
34512
23451
so the answer is 5! ways, divided by 5 that are considered the same=120/5=24.
5 people can be arranged 5! ways, however, since their relation to one another doesn't matter means that for every arrangement, there will be 4 others (5 total i.e. seats at the table) that are considered the same. thought of as an anagram,
12345 is the same as:
51234
45123
34512
23451
so the answer is 5! ways, divided by 5 that are considered the same=120/5=24.
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orel
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Hello guys,GMATters1001 wrote:Not knowing the formula for circular permutations:
5 people can be arranged 5! ways, however, since their relation to one another doesn't matter means that for every arrangement, there will be 4 others (5 total i.e. seats at the table) that are considered the same. thought of as an anagram,
12345 is the same as:
51234
45123
34512
23451
so the answer is 5! ways, divided by 5 that are considered the same=120/5=24.
is the formula always the same for circular arrangements: (n-1)! ?
and would the correct answer be 120, if the qustion asked to find the number of arrangements for 5 people on a round table?
thanks,
Feruza
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lunarpower
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the difference between a round table and a normal table is that a round table has no ends. therefore, you can arbitrarily select which seat is to be called seat #1.
two ways to approach this problem:
(1)
you can fix one of the people in place (or, equivalently, rotate the table like a carousel so that that person always winds up in the same place). this will avoid the production of multiple equivalent scenarios in which the people are seated in the same order, but have just shuffled a seat or two over (these don't count as different arrangements).
then you have free rein to arrange the other four people, so that's 4! = 24 arrangements.
(2)
alternatively, you can figure out that there are 5! = 120 arrangements overall.
however, each UNIQUE arrangement is actually repeated five times: because there are five seats at the table, there are 5 different versions of every possible seating arrangement. (for instance, ABCDE, BCDEA, CDEAB, DEABC, EABCD are all equivalent.)
so this means you must divide by 5: 120 / 5 = 24
two ways to approach this problem:
(1)
you can fix one of the people in place (or, equivalently, rotate the table like a carousel so that that person always winds up in the same place). this will avoid the production of multiple equivalent scenarios in which the people are seated in the same order, but have just shuffled a seat or two over (these don't count as different arrangements).
then you have free rein to arrange the other four people, so that's 4! = 24 arrangements.
(2)
alternatively, you can figure out that there are 5! = 120 arrangements overall.
however, each UNIQUE arrangement is actually repeated five times: because there are five seats at the table, there are 5 different versions of every possible seating arrangement. (for instance, ABCDE, BCDEA, CDEAB, DEABC, EABCD are all equivalent.)
so this means you must divide by 5: 120 / 5 = 24
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
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Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
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Learn more about ron
