QR formula confusion

[IWantH2O]

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topscore says that the number of ways of arranging "n" objects around a round table is (n-1)!...............but shouldnt be n! because that makes a lot more sense

 

[IWantH2O]

anybody

 

[tranv117]

i would help but math is like a foreign language to me right now since i havent started studying for it yet. I want to guess that it being a ROUND TABLE instead of a straight line has something to do with it.

 

[artanis]

Hey there,

the formula is correct. The time you use just n! is when you are in a straight line. If your doing round table questions, seat someone (place a 1) then the remainder of the people are placed in seats. multiply the number of people sitting in the seats, and this will be (n-1)!

 

[Streetwolf]

The correct formula is nPr / r. When n = r this simplifies to (n-1)!