1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Probability of 5 dice rolled

  1. Apr 18, 2007 #1
    When rolling 5 dice one time for each, what is the formula to figure the probability of getting a 5 of a kind, 4 of a kind, 3 of a kind, pair, and a straight.
    I used 6*(1/6*1/6*1/6*1/6*1/6) to get the probability of 5 of a kind and came up with 6/7776. What formulas do I use to get the others or how do I alter the formula?
    Last edited: Apr 18, 2007
  2. jcsd
  3. Apr 18, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

    You are off to a good start. The formula is (how many kinds)*(probability of getting n of the kind)*(how many ways to get the n). You've correctly done the five of a kind as 6*(1/6)^5*1. Now let's do 4. The first number is the same. The second number becomes (1/6)^4*(5/6) (four must be the selected number and the fifth can't). The last number is how many ways can this happen. Any of the 5 numbers can be nonmatching so 5. So 6*(1/6)^5*(5/6)*5. You can creatively make these up for each case, or you can think of some general formula you've been taught to apply. Hint: one of the numbers is called a combinatorial coefficient.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?