Mock AIME 1 Pre 2005 Problems/Problem 14

Problem

Wally's Key Company makes and sells two types of keys. Mr. Porter buys a total of 12 keys from Wally's. Determine the number of possible arrangements of My. Porter's 12 new keys on his keychain (rotations are considered the same and any two keys of the same type are identical).

Note: The problem is meant to be interpreted so that if you cannot produce one arrangement from another by rotation, then the two arrangements are different, even if you can produce one from the other from a combination of rotation and reflection.

Solution

See also

Mock AIME 1 Pre 2005 (Problems, Source)
Preceded by
Problem 13
Followed by
Problem 15
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
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