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by rakesh8403 » Thu Apr 28, 2011 5:58 am
please check and say whther its right or not

Boys = 4 ! , gals = 4!

no two boy and gals shld sit togethere so 2 ! * 2!

So ans is 4 ! * 4! / ( 2! * 2 !) = 144
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by rakesh8403 » Thu Apr 28, 2011 7:05 am
circular permutation for boys is (4-1) ! that is 3 ! and then gal can seat in 4 ! ways ..

so total = 4! * 3 ! = 144 ....
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by Anurag@Gurome » Thu Apr 28, 2011 9:12 pm
rakesh8403 wrote:circular permutation for boys is (4-1) ! that is 3 ! and then gal can seat in 4 ! ways ..

so total = 4! * 3 ! = 144 ....
That's right.
In Distinct arrangement: A circular arrangement of different people: For distinct objects the total number of permutations = (n - 1) !

Non-Distinct Arrangement: When the objects in the arrangement cannot be identified separately then the arrangement is non-distinct.
For non-distinct objects, both clockwise and anti-clockwise arrangement would be the same. Therefore, the total number of permutation = (n-1)!/2
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