Quandaries and Queries


Dear Math Central,

Why are locker combinations called locker combinations not locker permutations. The order of the numbers matter so why aren't they called locker permutations.

Level of question:Middle(6-9)




Hi Megan,

It is very nice of you to notice this distinction. I don't think that the locksmiths were taught about combinations and permutations though, so they just took the name "combinations" because it sounded nice. A course in permutations and combinations would have helped them figure out how safe were their locks though, by telling them how many "permutations" a thief would have to try before getting the right one.

Now that I think of it, are they really "permutations", or just "functions"? I think that you can repeat numbers, which makes even more possibilities.

There is also an answer to an earlier question where Chris and Penny have another interpretation of the origin of the word combinations.

Claude and Penny


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