In how many ways can be 6 boys and 6 girls sit around circular table so that no two boys sit next to each other?
A)(5!)^2
B)(6!)^2
C)5!6!
D)11!
E)(5!)^2 6!
I got (6!)^2 but the OA C
sitting arrangement
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For arrangements around a circular table:j_shreyans wrote:In how many ways can be 6 boys and 6 girls sit around circular table so that no two boys sit next to each other?
A)(5!)^2
B)(6!)^2
C)5!6!
D)11!
E)(5!)^2 6!
I got (6!)^2 but the OA C
1. First seat someone at the table.
2. Then count the number of ways to arrange the OTHER people relative to the first person.
In the problem above, no two boys can sit in adjacent seats.
Implication:
Boys and girls must ALTERNATE around the table.
Let the 12 seats be A, B, C, D, E, F, G, H, I, J, K, L.
Let a boy sit at seat A.
The remaining 5 boys must occupy seats C, E, G, I, and K.
The number of ways to arrange the remaining 5 boys in these 5 seats = 5!.
The 6 girls must occupy the remaining 6 seats.
The number of ways to arrange the 6 girls in these 6 seats = 6!.
To combine the options above, we multiply:
5!6!.
The correct answer is C.
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Followed here and elsewhere by over 1900 test-takers.
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].
Student Review #1
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