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10 milliards

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Krystal -  
 Duck -
Hello,

I would like to know the result (and the calculation method!) to determine the number of possible combinations for 10-digit numbers (0 1 2 3 4 5 6 7 8 9) knowing that the numbers start with 1, 2, 3, 4, or 5.
The digits can be used multiple times in the same number!
I was told about 1.8 million possibilities, but that seems low to me!
Thanks to whoever can help me!

Configuration: Windows 7 / Firefox 26.0

1 answer

  1.
    yannpl7 Posted messages 1535 Status Member 305
     
    Hello

    You can have 5,000,000,000 possibilities

    Explanations:
    for numbers starting with 1: you can have from 1,000,000,000 to 1,999,999,999, which is 1,000,000,000 possibilities
    for numbers starting with 2: you can have from 2,000,000,000 to 2,999,999,999, which is 1,000,000,000 possibilities
    ...
    So that's 5 x 1,000,000,000 = 5,000,000,000

    --
    he who holds knowledge holds power
    20
    1. Pierrecastor Posted messages 10830 Registration date   Status Moderator Last intervention   4 215
       
      Hi

      I would rather say 6,000,000,000 possibilities. From 0 to 5,999,999,999.
      1
      1. Duck > Pierrecastor Posted messages 10830 Registration date   Status Moderator Last intervention  
         

        Zero is not a digit, it's an addition; it creates a digit but it is not one because you can buy something with one euro, but with 0 € you can't buy anything.

        0
    2. yannpl7 Posted messages 1535 Status Member 305
       
      Well no, since the number starts with 1 or 2 or 3 or 4 or 5 and contains 10 digits.
      0
    3. Pierrecastor Posted messages 10830 Registration date   Status Moderator Last intervention   4 215
       
      Oh yes, well spotted.
      0