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Math Help - counting question

  1. #1
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    counting question

    The integers 1-25 are arranged in a 5x5 array (we use each number from 1 to 25 exactly once). All that matters is which numbers are in each column, and how they are arranged in the columns. It does not matter in which order the columns appear. How many different such arrays can be formed?
    I thought that the answer was 5!^5, but was told this was wrong. Could someone step me through how to do this?

    Thanks!
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  2. #2
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    Quote Originally Posted by absvalue View Post
    The integers 1-25 are arranged in a 5x5 array (we use each number from 1 to 25 exactly once). All that matters is which numbers are in each column, and how they are arranged in the columns. It does not matter in which order the columns appear. How many different such arrays can be formed?
    Surely the answer is (25)!.
    That is the number of ways to arrange the 25 numbers is queue.
    Put the first five in the first column, the next five in the second column, etc.
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  3. #3
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    Thanks. That makes sense.
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