Perms and Combs - Isn't a bracelet the same as a circle? (1 Viewer)

coyney

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I'm not sure as to how a) is any different to b) could someone please explain.
a) How many ways can 9 beads be arranged in a circle
8!
b) How many ways can 9 beads be arranged on a bracelet
Judging from the answer they've done 8!/2

Are they not the same thing?
 

Sy123

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I'm not sure as to how a) is any different to b) could someone please explain.
a) How many ways can 9 beads be arranged in a circle
8!
b) How many ways can 9 beads be arranged on a bracelet
Judging from the answer they've done 8!/2

Are they not the same thing?
A bracelet can be flipped to the other side, making every permutation identical to the one you get when you flip it, and thus you divide by 2

(i think)
 

braintic

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A bracelet can be flipped to the other side, making every permutation identical to the one you get when you flip it, and thus you divide by 2

(i think)
This situation is complicated somewhat when you have some identical beads.
 

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