Combinatorics

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 How many different four digit numbers can be made from the digits 2, 2, 2, 3 and 3?

Comments

  1. Anonymous18 November 2020 at 06:59

    Well, for this one you can do some casework:

    Case 1) Using 3 two's and a three.
    4! = 24
    24/3 = 8

    Case 2) Using 2 two's and 2 three's.
    4! = 24
    24/2 = 12
    12/2 = 6

    Now we have both cases answered giving us 8 + 6 ( the answers from the cases) which is 14

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