Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Mathematics (https://www.askmehelpdesk.com/forumdisplay.php?f=199)
-   -   Probablity Again (https://www.askmehelpdesk.com/showthread.php?t=143423)

  • Oct 22, 2007, 02:15 AM
    Confused_111
    Probablity Again
    Hi there this question really stumped me...

    A die is rolled three time. The probablity of getting at least one odd number is what? A tree diagram would be too long to do and the lattice might be useful, other than that I have no clue on how to do it.

    Thanks
  • Oct 22, 2007, 02:22 AM
    colbtech
    Evens? (1:1) Each roll offers the same odds, 3 odd number 3 even numbers.
  • Oct 22, 2007, 02:30 AM
    Confused_111
    I'm sorry, I am still a bit lost Iget what your trying to say. Do I cube root it or something.
    Thanks
  • Oct 22, 2007, 02:36 AM
    Capuchin
    What's the probability of getting no odd numbers? Therefore, what's the probability of getting at least one odd number?
  • Oct 22, 2007, 02:53 AM
    Confused_111
    No odd numbers out of the three roles??
  • Oct 22, 2007, 02:56 AM
    Capuchin
    Yes, that should be very simple to work out, then you just work out the probability of NOT getting that outcome.
  • Oct 22, 2007, 03:09 AM
    Confused_111
    Oh I see, its so simple. Would it be any chance by Pr of 7/8 of getting at least one odd number
  • Oct 22, 2007, 03:16 AM
    terryg752
    How not to get any odd number:

    Each time : must be from 2, 4, 6

    Each time: Number of ways to get even no. = 3
    Number of ways to get any number = 6

    Each time dice is rolled, probability of even number = 3/6 = 1/2

    Probability getting Only even numbers 3 times is (1/2)^3 = 1/8

    Probability : At least one odd number: = 1 - 1/8 = 7/8
  • Oct 22, 2007, 08:23 AM
    galactus
    Agree with Terry.

    By the binomial probability.


  • All times are GMT -7. The time now is 07:55 PM.