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I need to generate a list of combination

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    I need to generate a list of combination

    Hello! I need some help from you. I want to list all possible combinations for this problem. I have 20 questions and each has 3 answers: a, b, c. Only one is correct. What i have to do? How many posibilities are? i can use xcel? I am a newbie and not so advanced in excel. Thank you!

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    Re: I need to generate a list of combination

    It's not practical.

    There are 3^20 possible different combinations -- that's over 3 trillion. If you listed each possible combination in a single Excel 2003 cell, it would require 208 worksheets and over 100GB of disk storage.
    Entia non sunt multiplicanda sine necessitate

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    Re: I need to generate a list of combination

    I don't believe that are so many. The formula COMBIN (20,3), is not ok?

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    Re: I need to generate a list of combination

    Quote Originally Posted by shg View Post
    It's not practical.

    There are 3^20 possible different combinations -- that's over 3 trillion. If you listed each possible combination in a single Excel 2003 cell, it would require 208 worksheets and over 100GB of disk storage.
    Shg is right about the possible number of combinations from a Questionnaire with 20 Q each with 3 possible answers. But i think we missunderstand want to do, please try and explain what you are trying to achieve.

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    Re: I need to generate a list of combination

    I have a set of 20 questions, each with 3 answer (a,b,c) and only one is correct. I want to generate a list with all the posibilities of combinations and one to be the correct one. I hope that you understand.

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    Re: I need to generate a list of combination

    If there were one one question, there are three possible results: a, b, and c.

    If there were two questions, there would be 9: aa, ab, ac, ba, bb, bc, ca, cb, cc

    If there were three, 27: aaa, aab, aac, aba, abb, abc, aca, acb, acc, baa, ... , ccb, ccc

    For four questions, 81

    For five questions, 243

    For 20 questions, 3,486,784,401

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    Re: I need to generate a list of combination

    My mistake... Thank you for your answers. My shame for beliieving that are only 1140 combinations. I think that i have to choose only 9 or 10 question to achive something. Could you tell me how to do the list for 10 questions?

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    Re: I need to generate a list of combination

    If the list is to long, for 6-7 question and i hope to can reduce the number of combinitions using for some questions the answer at a, b. It is posibile to generate a dieferent list with only 2 answers?

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    Re: I need to generate a list of combination

    See http://www.box.net/shared/ubd28tissi.

    Insert columns until there are 10, and put a b c in each of the symbol ranges. Copy the formulas across than then down. The first few rows will look like this:

    Please Login or Register  to view this content.

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    Re: I need to generate a list of combination

    i'm trying the thing that you told me, but i can't do the thing. My table doesn't work. could you send me another model with a,b,c that you make it in .xls? i don't understand how it works that chinese menu.

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    Re: I need to generate a list of combination

    thank you! i did it!

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