Quandaries and Queries


Name: Debora

question in critical thinking
I'm a student at the University of Phoenix.

Question is:
An anthropologist discovers an isolated tribe whose written alphabet contains only six letters (call the letters A, B, C, D, E, and F). The tribe has a taboo against using the same letter twice in the same word. It's never done. If each different sequence of letters constitutes a different work in the language, what is the maximum number of six- letter words that the language can employ?

I would appreciate any help you can give me on this.
Thank you,



Hi Debora,

I think of having a supply of Scrabble tiles with the letters A, B, C, D, E and F on them, and I am going to form all possible 6 letter words with no letter repeated in a word. Start by choosing a letter for the first letter of the word. There are 6 choices.

Now add a second letter. Regardless of the letter you chose for the first letter in the word, there are 5 choices for the second letter. Thus you have 65=30 two letter words. Here are ten of them, the ones that start with A or B.

Now add a third letter. Regardless of the letters you chose for the first two letters in the word, there are 4 choices for the third letter. Thus you have 654=1200 three letter words.

Can you complete it now?



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