Ask Experts Questions for FREE Help !
Ask
    sirpilf's Avatar
    sirpilf Posts: 1, Reputation: 1
    New Member
    		  
    #1

    Feb 17, 2009, 06:59 PM
    probability of three fair dice
    I am taking stats modeling, its suppose to be a 5000 level course, but right now I have doing review homework, its been 2 years since prob, and this problem is driving me crazy. It should only take 2 min and I can't for gods sake get it.

    roll three 6 sided fair dice, what's probability that you get exactly 2 dice with the same number, so the 3rd dice must be a different number.

    in this first chapter, we have not done binomials yet, and I thought it was just 1 * (1/6) * (5/6) = 5/36. But its wrong, how do I do this?
    galactus's Avatar
    galactus Posts: 2,271, Reputation: 282
    Ultra Member
    		  
    #2

    Feb 18, 2009, 06:10 AM
    Don't forget your factorial. There are to the same out of three. It could be the first and second, second and third or first and third. Multiply by 3.

    We have 3 die and 2 are the same,
    reinsuranc's Avatar
    reinsuranc Posts: 92, Reputation: 6
    Junior Member
    		  
    #3

    Feb 20, 2009, 04:15 PM
    The probability of getting exactly two 1's is 3*[(1/6)^2]*(5/6) = 15/216.

    (The 3 takes care of which of the three dice gives doubles - there are 3 possibilities.

    The probability of getting exactly two of any number is 6 times that, or 90/216.
Not your question? Ask your question View similar questions
 

Question Tools Search this Question
Search this Question:

Advanced Search


Check out some similar questions!

Moose dice game [ 1 Answers ]

I have a game called Moose.. there are 6 dice and each one is numbered... moose, 2, 3, 4, 5, 6... I haven't played it for years and cannot remember how it is scored or the basic rules of play... does anyone know how this dice game is played?

Dice Probability [ 3 Answers ]

Suppose you roll 4 dice. a) What is the probability that you get 4 different numbers? b) What is the probability that you get '2 pairs' (two of one number and two of another number?) c) Now suppose that you continue rolling 4 dice over and over until you get either get '4 different...

Dice probability [ 1 Answers ]

Dice

Probability for dice roll outcomes [ 2 Answers ]

I have searched for similar answers with no luck so I am hoping one of you can be kind enough to help me with this. Using standard 6 sided die - all results should be based on only one roll for each question of the following number of die. Each question below is independent of other questions,...

Dice [ 1 Answers ]

Which of these events is more likely? A) At least one six is obtained when six dice are rolled. B) At least two sixes are obtained when 12 dice are rolled. C) At least 3 sixes are obtained when 18 dice are rolled.

View more questions Search