Thread: combinations

Your making a necklace with 4 red peices and 4 yellow peices. How many different combination of necklaces can you make?

is 2^8 correct.

2^8 is not correct.

Here's why:
2^8 assumes a necklace like:
RYRYRYRY
is different than a necklace like:
YRYRYRYR

You need to reflect this in your counting to obtain the correct (i.e. lower) answer.

Hello, harold3331!

This is a very tricky problem . . .

You're making a necklace with 4 red pieces and 4 yellow pieces.
How many different combination of necklaces can you make?

is 2^8 correct? . . . . no

Your answer assumes there are at least eight of each color
. . and includes all the combinations from


Even worse, this is a necklace . . . a circular arrangement.
So that, for example: .

. . That is: . . .



There is one more "trap" in a Necklace Problem, overlooked by the best of us.

This is similar to seating 4 men and 4 women around a circilar table,
. . except a necklace can be "flipped over".

So that: . . .


Care to try again?